P89LPC920/921/922/9221 8-bit microcontrollers with two ... · PDF filePhilips Semiconductors...

P89LPC920/921/922/92218-bit microcontrollers with two-clock 80C51 core2 kB/4 kB/8 kB 3 V low-power Flash with 256-byte data RAMRev. 08 — 15 December 2004 Product data

1. General description

The P89LPC920/921/922/9221 are single-chip microcontrollers designed forapplications demanding high-integration, low cost solutions over a wide range ofperformance requirements. The P89LPC920/921/922/9221 is based on a highperformance processor architecture that executes instructions in two to four clocks,six times the rate of standard 80C51 devices. Many system-level functions have beenincorporated into the P89LPC920/921/922/9221 in order to reduce component count,board space, and system cost.

2. Features

2.1 Principal features 2 kB/4 kB/8 kB Flash code memory with 1 kB erasable sectors, 64-byte erasable

page size, and single byte erase.

256-byte RAM data memory.

Two 16-bit counter/timers. Each timer may be configured to toggle a port outputupon timer overflow or to become a PWM output.

Real-Time clock that can also be used as a system timer.

Two analog comparators with selectable inputs and reference source.

Enhanced UART with fractional baud rate generator, break detect, framing errordetection, automatic address detection and versatile interrupt capabilities.

400 kHz byte-wide I2C-bus communication port.

Configurable on-chip oscillator with frequency range and RC oscillator options(selected by user programmed Flash configuration bits). The RC oscillator (factorycalibrated to ±1 %) option allows operation without external oscillatorcomponents. Oscillator options support frequencies from 20 kHz to the maximumoperating frequency of 18 MHz. The RC oscillator option is selectable and finetunable.

2.4 V to 3.6 V VDD operating range. I/O pins are 5 V tolerant (may be pulled up ordriven to 5.5 V).

High drive current (20 mA) on eight I/O pins on the P89LPC9221 (P0.3 to P0.7,P1.4, P1.6, P1.7).

Philips Semiconductors P89LPC920/921/922/92218-bit microcontrollers with two-clock 80C51 core

2.2 Additional features 15 I/O pins minimum. Up to 18 I/O pins while using on-chip oscillator and reset

options.

20-pin TSSOP and DIP packages.

A high performance 80C51 CPU provides instruction cycle times of 111 ns to222 ns for all instructions except multiply and divide when executing at 18 MHz.This is six times the performance of the standard 80C51 running at the sameclock frequency. A lower clock frequency for the same performance results inpower savings and reduced EMI.

In-Application Programming of the Flash code memory. This allows changing thecode in a running application.

Serial Flash programming allows simple in-circuit production coding. Flashsecurity bits prevent reading of sensitive application programs.

Watchdog timer with separate on-chip oscillator, requiring no externalcomponents. The watchdog prescaler is selectable from eight values.

Low voltage reset (Brownout detect) allows a graceful system shutdown whenpower fails. May optionally be configured as an interrupt.

Idle and two different Power-down reduced power modes. Improved wake-up fromPower-down mode (a low interrupt input starts execution). Typical Power-downcurrent is 1 µA (total Power-down with voltage comparators disabled).

Active-LOW reset. On-chip power-on reset allows operation without external resetcomponents. A reset counter and reset glitch suppression circuitry preventspurious and incomplete resets. A software reset function is also available.

Oscillator Fail Detect. The watchdog timer has a separate fully on-chip oscillatorallowing it to perform an oscillator fail detect function.

Programmable port output configuration options:

quasi-bidirectional,

open drain,

push-pull,

input-only.

Port ‘input pattern match’ detect. Port 0 may generate an interrupt when the valueof the pins match or do not match a programmable pattern.

LED drive capability (20 mA) on all port pins. A maximum limit is specified for theentire chip (160 mA for the P89LPC9221; 80 mA for the P89LPC920/921/922).

Controlled slew rate port outputs to reduce EMI. Outputs have approximately10 ns minimum ramp times.

Only power and ground connections are required to operate theP89LPC920/921/922/9221 when internal reset option is selected.

Four interrupt priority levels.

Eight keypad interrupt inputs, plus two additional external interrupt inputs.

Second data pointer.

Schmitt trigger port inputs.

Emulation support.

Product data Rev. 08 — 15 December 2004 2 of 46

9397 750 14469 © Koninklijke Philips Electronics N.V. 2004. All rights reserved.


3. Ordering information

3.1 Ordering options

Table 1: Ordering information

Type number Package

Name Description Version

P89LPC920FDH TSSOP20 plastic thin shrink small outline package;20 leads; body width 4.4 mm

SOT360-1


SOT360-1


SOT360-1

P89LPC922FN DIP20 plastic dual in-line package; 20 leads (300 mil) SOT146-1

P89LPC9221FN DIP20 plastic dual in-line package; 20 leads (300 mil) SOT146-1


SOT360-1

Table 2: Part options

Type number Flash memory Temperature range Frequency

P89LPC920FDH 2 kB −40 °C to +85 °C 0 MHz to 18 MHz



P89LPC922FN 8 kB −40 °C to +85 °C 0 MHz to 18 MHz

P89LPC9221FN 8 kB −40 °C to +85 °C 0 MHz to 18 MHz





4. Block diagram

Fig 1. Block diagram.

HIGH PERFORMANCEACCELERATED 2-CLOCK 80C51 CPU

2 kB/4 kB/8 kBCODE FLASH

256-BYTEDATA RAM

PORT 3CONFIGURABLE I/Os



KEYPADINTERRUPT

PROGRAMMABLEOSCILLATOR DIVIDER CPU

clock

CONFIGURABLEOSCILLATOR

ON-CHIPRC

OSCILLATOR

internal bus

CRYSTALOR

RESONATOR

POWER MONITOR(POWER-ON RESET, BROWNOUT RESET)

002aaa410

UART

REAL-TIME CLOCK/SYSTEM TIMER

I2C

TIMER 0TIMER 1

WATCHDOG TIMERAND OSCILLATOR

ANALOGCOMPARATORS

P89LPC920/921/922/9221




5. Pinning information

5.1 Pinning

Fig 2. TSSOP20 pin configuration.

Fig 3. DIP20 pin configuration.

handbook, halfpage

P89

LPC

920F

DH

P89

LPC

921F

DH

P89

LPC

922F

DH

P89

LPC

9221

FD

H

002aaa408

1

2

3

4

5

6

7

8

9

10

KBI0/CMP2/P0.0

P1.7

P1.6

RST/P1.5

VSS

XTAL1/P3.1

CLKOUT/XTAL2/P3.0

INT1/P1.4

SDA/INT0/P1.3

SCL/T0/P1.2

P0.1/CIN2B/KBI1

P0.2/CIN2A/KBI2

P0.3/CIN1B/KBI3

P0.4/CIN1A/KBI4

P0.5/CMPREF/KBI5

VDD

P0.6/CMP1/KBI6

P0.7/T1/KBI7

P1.0/TXD

P1.1/RXD

20

19

18

17

16

15

14

13

12

11

handbook, halfpage

P89

LPC

922F

NP

89LP

C92

21F

N

002aaa407

1

2

3

4

5

6

7

8

9

10

KBI0/CMP2/P0.0

P1.7

P1.6

RST/P1.5

VSS

XTAL1/P3.1

CLKOUT/XTAL2/P3.0

INT1/P1.4

SDA/INT0/P1.3

SCL/T0/P1.2

P0.1/CIN2B/KBI1

P0.2/CIN2A/KBI2

P0.3/CIN1B/KBI3

P0.4/CIN1A/KBI4

P0.5/CMPREF/KBI5

VDD

P0.6/CMP1/KBI6

P0.7/T1/KBI7

P1.0/TXD

P1.1/RXD

20

19

18

17

16

15

14

13

12

11




5.2 Pin description

Table 3: Pin description

Symbol Pin Type Description

P0.0 to P0.7 I/O Port 0: Port 0 is an 8-bit I/O port with a user-configurable output type. During resetPort 0 latches are configured in the input only mode with the internal pull-up disabled.The operation of Port 0 pins as inputs and outputs depends upon the port configurationselected. Each port pin is configured independently. Refer to Section 8.12.1 “Portconfigurations” and Table 8 “DC electrical characteristics” for details.

The Keypad Interrupt feature operates with Port 0 pins.

All pins have Schmitt triggered inputs.

Port 0 also provides various special functions as described below:

1 I/O P0.0 — Port 0 bit 0.

O CMP2 — Comparator 2 output.

I KBI0 — Keyboard input 0.

20 I/O P0.1 — Port 0 bit 1.

I CIN2B — Comparator 2 positive input B.


19 I/O P0.2 — Port 0 bit 2.

I CIN2A — Comparator 2 positive input A.


18 I/O P0.3 — Port 0 bit 3. High current source (P89LPC9221).

I CIN1B — Comparator 1 positive input B.



I CIN1A — Comparator 1 positive input A.



I CMPREF — Comparator reference (negative) input.



O CMP1 — Comparator 1 output.



I/O T1 — Timer/counter 1 external count input or overflow output.





P1.0 to P1.7 I/O, I [1] Port 1: Port 1 is an 8-bit I/O port with a user-configurable output type, except for threepins as noted below. During reset Port 1 latches are configured in the input only modewith the internal pull-up disabled. The operation of the configurable Port 1 pins as inputsand outputs depends upon the port configuration selected. Each of the configurableport pins are programmed independently. Refer to Section 8.12.1 “Port configurations”and Table 8 “DC electrical characteristics” for details. P1.2 - P1.3 are open drain whenused as outputs. P1.5 is input only.



12 I/O P1.0 — Port 1 bit 0.

O TXD — Transmitter output for the serial port.

11 I/O P1.1 — Port 1 bit 1.

I RXD — Receiver input for the serial port.

10 I/O P1.2 — Port 1 bit 2 (open-drain when used as output).

I/O T0 — Timer/counter 0 external count input or overflow output (open-drain when used asoutput).

I/O SCL — I2C serial clock input/output.

9 I/O P1.3 — Port 1 bit 3 (open-drain when used as output).

I INT0 — External interrupt 0 input.

I/O SDA — I2C serial data input/output.


I INT1 — External interrupt 1 input.

4 I P1.5 — Port 1 bit 5 (input only).

I RST — External Reset input (if selected via FLASH configuration). A LOW on this pinresets the microcontroller, causing I/O ports and peripherals to take on their defaultstates, and the processor begins execution at address 0. When using an oscillatorfrequency above 12 MHz, the reset input function of P1.5 must be enabled. Anexternal circuit is required to hold the device in reset at power-up until V DD hasreached its specified level. When system power is removed V DD will fall below theminimum specified operating voltage. When using an oscillator frequency above12 MHz, in some applications, an external brownout detect circuit may berequired to hold the device in reset when V DD falls below the minimum specifiedoperating voltage.



Table 3: Pin description …continued





[1] Input/Output for P1.0-P1.4, P1.6, P1.7. Input for P1.5.

6. Logic symbol

P3.0 to P3.1 I/O Port 3: Port 3 is an 2-bit I/O port with a user-configurable output type. During resetPort 3 latches are configured in the input only mode with the internal pull-up disabled.The operation of Port 3 pins as inputs and outputs depends upon the port configurationselected. Each port pin is configured independently. Refer to Section 8.12.1 “Portconfigurations” and Table 8 “DC electrical characteristics” for details.



7 I/O P3.0 — Port 3 bit 0.

O XTAL2 — Output from the oscillator amplifier (when a crystal oscillator option isselected via the FLASH configuration.

O CLKOUT — CPU clock divided by 2 when enabled via SFR bit (ENCLK - TRIM.6). Itcan be used if the CPU clock is the internal RC oscillator, watchdog oscillator orexternal clock input, except when XTAL1/XTAL2 are used to generate clock source forthe real time clock/system timer.

6 I/O P3.1 — Port 3 bit 1.

I XTAL1 — Input to the oscillator circuit and internal clock generator circuits (whenselected via the FLASH configuration). It can be a port pin if internal RC oscillator orwatchdog oscillator is used as the CPU clock source, and if XTAL1/XTAL2 are not usedto generate the clock for the real time clock/system timer.

VSS 5 I Ground: 0 V reference.

VDD 15 I Power Supply: This is the power supply voltage for normal operation as well as Idleand Power down modes.

Table 3: Pin description …continued


Fig 4. Logic symbol.

VDD VSS

P89

LPC

920/

921/

922/

9221

PO

RT

0P

OR

T 3

PO

RT

1

TxDRxDT0INT0INT1RST

SCLSDA

002aaa409

CMP2CIN2BCIN2ACIN1BCIN1A

CMPREFCMP1

T1

XTAL2

XTAL1

KBI0KBI1KBI2KBI3KBI4KBI5KBI6KBI7

CLKOUT




7. Special function registers

Remark: Special Function Registers (SFRs) accesses are restricted in the followingways:

• User must not attempt to access any SFR locations not defined.

• Accesses to any defined SFR locations must be strictly for the functions for theSFRs.

• SFR bits labeled ‘-’, ‘0’ or ‘1’ can only be written and read as follows:

– ‘-’ Unless otherwise specified, must be written with ‘0’, but can return any valuewhen read (even if it was written with ‘0’). It is a reserved bit and may be used infuture derivatives.

– ‘0’ must be written with ‘0’, and will return a ‘0’ when read.

– ‘1’ must be written with ‘1’, and will return a ‘1’ when read.



xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxx x x x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xx xxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxx x xxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxx xxx P

hilips Sem

iconductorsP

89LPC

920/921/922/92218-bit m

icrocontrollers with tw

o-clock 80C51 core

9397 750 14469©

Koninklijke P

hilips Electronics N

.V. 2004. All rights reserved.

Product data

Rev. 08 —

15 Decem

ber 200410 of 46

Table 4: Special function registers* indicates SFRs that are bit addressable.

Reset value

LSB Hex Binary

E0

00 00000000

DPS 00[1] 000000x0

F0

00 00000000

00 00000000

00 00000000

BRGEN 00 xxxxxx00

CMF1 00[1] xx000000

CMF2 00[1] xx000000

00 00000000

00 00000000

00 00000000

00 00000000

00 00000000

OI 70 01110000

FMCMD.0

00 00000000

GC 00 00000000

D8

CRSEL 00 x00000x0

00 00000000

Name Description SFRaddr.

Bit functions and addresses

MSB

Bit address E7 E6 E5 E4 E3 E2 E1

ACC* Accumulator E0H

AUXR1 Auxiliary function register A2H CLKLP EBRR ENT1 ENT0 SRST 0 -

Bit address F7 F6 F5 F4 F3 F2 F1

B* B register F0H

BRGR0[2] Baud rate generator rateLOW

BEH

BRGR1[2] Baud rate generator rateHIGH

BFH

BRGCON Baud rate generator control BDH - - - - - - SBRGS

CMP1 Comparator 1 control register ACH - - CE1 CP1 CN1 OE1 CO1

CMP2 Comparator 2 control register ADH - - CE2 CP2 CN2 OE2 CO2

DIVM CPU clock divide-by-Mcontrol

95H

DPTR Data pointer (2 bytes)

DPH Data pointer HIGH 83H

DPL Data pointer LOW 82H

FMADRH Program Flash address HIGH E7H

FMADRL Program Flash address LOW E6H

FMCON Program Flash control (Read) E4H BUSY - - - HVA HVE SV

Program Flash control (Write) E4H FMCMD.7

FMCMD.6

FMCMD.5

FMCMD.4

FMCMD.3

FMCMD.2

FMCMD.1

FMDATA Program Flash data E5H

I2ADR I2C slave address register DBH I2ADR.6 I2ADR.5 I2ADR.4 I2ADR.3 I2ADR.2 I2ADR.1 I2ADR.0

Bit address DF DE DD DC DB DA D9

I2CON* I2C control register D8H - I2EN STA STO SI AA -

I2DAT I2C data register DAH

I2SCLH Serial clock generator/SCLduty cycle register HIGH

DDH


hilips Sem

iconductorsP

89LPC

920/921/922/92218-bit m


o-clock 80C51 core

9397 750 14469©

Koninklijke P



Product data

Rev. 08 —

15 Decem

ber 200411 of 46

00 00000000

0 F8 11111000

A8

EX0 00[1] 00000000

E8

EI2C 00[1] 00x00000

B8

PX0 00[1] x0000000

PX0H 00[1] x0000000

F8

PI2C 00[1] 00x00000

PI2CH 00[1] 00x00000

KBIF 00[1] xxxxxx00

00 00000000

FF 11111111

80

CMP2/KB0

[1]

90

TXD [1]

B0

XTAL2 [1]

(P0M1.0) FF 11111111

(P0M2.0) 00 00000000

(P1M1.0) D3[1] 11x1xx11

Table 4: Special function registers …continued* indicates SFRs that are bit addressable.

Reset value

LSB Hex Binary

I2SCLL Serial clock generator/SCLduty cycle register LOW

DCH

I2STAT I2C status register D9H STA.4 STA.3 STA.2 STA.1 STA.0 0 0

Bit address AF AE AD AC AB AA A9

IEN0* Interrupt enable 0 A8H EA EWDRT EBO ES/ESR ET1 EX1 ET0

Bit address EF EE ED EC EB EA E9

IEN1* Interrupt enable 1 E8H - EST - - - EC EKBI

Bit address BF BE BD BC BB BA B9

IP0* Interrupt priority 0 B8H - PWDRT PBO PS/PSR PT1 PX1 PT0

IP0H Interrupt priority 0 HIGH B7H - PWDRTH

PBOH PSH/PSRH

PT1H PX1H PT0H

Bit address FF FE FD FC FB FA F9

IP1* Interrupt priority 1 F8H - PST - - - PC PKBI

IP1H Interrupt priority 1 HIGH F7H - PSTH - - - PCH PKBIH

KBCON Keypad control register 94H - - - - - - PATN_SEL

KBMASK Keypad interrupt maskregister

86H

KBPATN Keypad pattern register 93H

Bit address 87 86 85 84 83 82 81

P0* Port 0 80H T1/KB7 CMP1/KB6

CMPREF/KB5

CIN1A/KB4

CIN1B/KB3

CIN2A/KB2

CIN2B/KB1

Bit address 97 96 95 94 93 92 91

P1* Port 1 90H - - RST INT1 INT0/SDA

T0/SCL RXD

Bit address B7 B6 B5 B4 B3 B2 B1

P3* Port 3 B0H - - - - - - XTAL1

P0M1 Port 0 output mode 1 84H (P0M1.7) (P0M1.6) (P0M1.5) (P0M1.4) (P0M1.3) (P0M1.2) (P0M1.1)

P0M2 Port 0 output mode 2 85H (P0M2.7) (P0M2.6) (P0M2.5) (P0M2.4) (P0M2.3) (P0M2.2) (P0M2.1)

P1M1 Port 1 output mode 1 91H (P1M1.7) (P1M1.6) - (P1M1.4) (P1M1.3) (P1M1.2) (P1M1.1)



MSB


hilips Sem

iconductorsP

89LPC

920/921/922/92218-bit m


o-clock 80C51 core

9397 750 14469©

Koninklijke P



Product data

Rev. 08 —

15 Decem

ber 200412 of 46

(P1M2.0) 00[1] 00x0xx00

(P3M1.0) 03[1] xxxxxx11

(P3M2.0) 00[1] xxxxxx00

PMOD0 00 00000000

- 00[1] 00000000

D0

P 00H 00000000

- 00H xx00000x

R_EX [3]

RTCEN 60[1][6]

00[6] 00000000

00[6] 00000000

00 00000000

00 00000000

xx xxxxxxxx

98

RI 00 00000000

STINT 00 00000000

07 00000111

T0M2 00 xxx0xxx0

88

IT0 00 00000000

00 00000000

00 00000000

00 00000000

00 00000000

T0M0 00 00000000


Reset value

LSB Hex Binary

P1M2 Port 1 output mode 2 92H (P1M2.7) (P1M2.6) - (P1M2.4) (P1M2.3) (P1M2.2) (P1M2.1)

P3M1 Port 3 output mode 1 B1H - - - - - - (P3M1.1)

P3M2 Port 3 output mode 2 B2H - - - - - - (P3M2.1)

PCON Power control register 87H SMOD1 SMOD0 BOPD BOI GF1 GF0 PMOD1

PCONA Power control register A B5H RTCPD - VCPD - I2PD - SPD

Bit address D7 D6 D5 D4 D3 D2 D1

PSW* Program status word D0H CY AC F0 RS1 RS0 OV F1

PT0AD Port 0 digital input disable F6H - - PT0AD.5 PT0AD.4 PT0AD.3 PT0AD.2 PT0AD.1

RSTSRC Reset source register DFH - - BOF POF R_BK R_WD R_SF

RTCCON Real-time clock control D1H RTCF RTCS1 RTCS0 - - - ERTC

RTCH Real-time clock registerHIGH

D2H

RTCL Real-time clock register LOW D3H

SADDR Serial port address register A9H

SADEN Serial port address enable B9H

SBUF Serial Port data bufferregister

99H

Bit address 9F 9E 9D 9C 9B 9A 99

SCON* Serial port control 98H SM0/FE SM1 SM2 REN TB8 RB8 TI

SSTAT Serial port extended statusregister

BAH DBMOD INTLO CIDIS DBISEL FE BR OE

SP Stack pointer 81H

TAMOD Timer 0 and 1 auxiliary mode 8FH - - - T1M2 - - -

Bit address 8F 8E 8D 8C 8B 8A 89

TCON* Timer 0 and 1 control 88H TF1 TR1 TF0 TR0 IE1 IT1 IE0

TH0 Timer 0 HIGH 8CH

TH1 Timer 1 HIGH 8DH

TL0 Timer 0 LOW 8AH

TL1 Timer 1 LOW 8BH

TMOD Timer 0 and 1 mode 89H T1GATE T1C/T T1M1 T1M0 T0GATE T0C/T T0M1



MSB


hilips Sem

iconductorsP

89LPC

920/921/922/92218-bit m


o-clock 80C51 core

9397 750 14469©

Koninklijke P



Product data

Rev. 08 —

15 Decem

ber 200413 of 46

xcept POF and BOF; the power-on

after power-on reset. Other resets will

ister.

TRIM.0 [5] [6]

WDCLK [4] [6]

FF 11111111


Reset value

LSB Hex Binary

[1] All ports are in input only (high impedance) state after power-up.

[2] BRGR1 and BRGR0 must only be written if BRGEN in BRGCON SFR is ‘0’. If any are written while BRGEN = 1, the result is unpredictable.

[3] The RSTSRC register reflects the cause of the P89LPC920/921/922/9221 reset. Upon a power-up reset, all reset source flags are cleared ereset value is xx110000.

[4] After reset, the value is 111001x1, i.e., PRE2-PRE0 are all ‘1’, WDRUN = 1 and WDCLK = 1. WDTOF bit is ‘1’ after watchdog reset and is ‘0’not affect WDTOF.

[5] On power-on reset, the TRIM SFR is initialized with a factory preprogrammed value. Other resets will not cause initialization of the TRIM reg

[6] The only reset source that affects these SFRs is power-on reset.

TRIM Internal oscillator trim register 96H - ENCLK TRIM.5 TRIM.4 TRIM.3 TRIM.2 TRIM.1

WDCON Watchdog control register A7H PRE2 PRE1 PRE0 - - WDRUN WDTOF

WDL Watchdog load C1H

WFEED1 Watchdog feed 1 C2H

WFEED2 Watchdog feed 2 C3H



MSB


8. Functional description

Remark: Please refer to the P89LPC920/921/922/9221 User’s Manual for a moredetailed functional description.

8.1 Enhanced CPUThe P89LPC920/921/922/9221 uses an enhanced 80C51 CPU which runs at 6 timesthe speed of standard 80C51 devices. A machine cycle consists of two CPU clockcycles, and most instructions execute in one or two machine cycles.

8.2 Clocks

8.2.1 Clock definitions

The P89LPC920/921/922/9221 device has several internal clocks as defined below:

OSCCLK — Input to the DIVM clock divider. OSCCLK is selected from one of fourclock sources (see Figure 5) and can also be optionally divided to a slower frequency(see Section 8.7 “CPU Clock (CCLK) modification: DIVM register”).

Note: fosc is defined as the OSCCLK frequency.

CCLK — CPU clock; output of the clock divider. There are two CCLK cycles permachine cycle, and most instructions are executed in one to two machine cycles (twoor four CCLK cycles).

RCCLK — The internal 7.373 MHz RC oscillator output.

PCLK — Clock for the various peripheral devices and is CCLK/2

8.2.2 CPU clock (OSCCLK)

The P89LPC920/921/922/9221 provides several user-selectable oscillator options ingenerating the CPU clock. This allows optimization for a range of needs from highprecision to lowest possible cost. These options are configured when the FLASH isprogrammed and include an on-chip watchdog oscillator, an on-chip RC oscillator, anoscillator using an external crystal, or an external clock source. The crystal oscillatorcan be optimized for low, medium, or high frequency crystals covering a range from20 kHz to 12 MHz.

8.2.3 Low speed oscillator option

This option supports an external crystal in the range of 20 kHz to 100 kHz. Ceramicresonators are also supported in this configuration.

8.2.4 Medium speed oscillator option

This option supports an external crystal in the range of 100 kHz to 4 MHz. Ceramicresonators are also supported in this configuration.

8.2.5 High speed oscillator option

This option supports an external crystal in the range of 4 MHz to 18 MHz. Ceramicresonators are also supported in this configuration. When using an oscillatorfrequency above 12 MHz, the reset input function of P1.5 must be enabled. Anexternal circuit is required to hold the device in reset at power-up until V DD hasreached its specified level. When system power is removed V DD will fall below




the minimum specified operating voltage. When using an oscillator frequencyabove 12 MHz, in some applications, an external brownout detect circuit maybe required to hold the device in reset when V DD falls below the minimumspecified operating voltage.

8.2.6 Clock output

The P89LPC920/921/922/9221 supports a user-selectable clock output function onthe XTAL2/CLKOUT pin when crystal oscillator is not being used. This conditionoccurs if another clock source has been selected (on-chip RC oscillator, watchdogoscillator, external clock input on X1) and if the Real-Time clock is not using thecrystal oscillator as its clock source. This allows external devices to synchronize tothe P89LPC920/921/922/9221. This output is enabled by the ENCLK bit in the TRIMregister. The frequency of this clock output is 1⁄2 that of the CCLK. If the clock outputis not needed in Idle mode, it may be turned off prior to entering Idle, savingadditional power.

8.3 On-chip RC oscillator optionThe P89LPC920/921/922/9221 has a 6-bit TRIM register that can be used to tune thefrequency of the RC oscillator. During reset, the TRIM value is initialized to a factorypre-programmed value to adjust the oscillator frequency to 7.373 MHz, ±1% at roomtemperature. End-user applications can write to the Trim register to adjust the on-chipRC oscillator to other frequencies.

8.4 Watchdog oscillator optionThe watchdog has a separate oscillator which has a frequency of 400 kHz. Thisoscillator can be used to save power when a high clock frequency is not needed.

8.5 External clock input optionIn this configuration, the processor clock is derived from an external source drivingthe XTAL1/P3.1 pin. The rate may be from 0 Hz up to 12 MHz. The XTAL2/P3.0 pinmay be used as a standard port pin or a clock output. When using an oscillatorfrequency above 12 MHz, the reset input function of P1.5 must be enabled. Anexternal circuit is required to hold the device in reset at power-up until V DD hasreached its specified level. When system power is removed V DD will fall belowthe minimum specified operating voltage. When using an oscillator frequencyabove 12 MHz, in some applications, an external brownout detect circuit maybe required to hold the device in reset when V DD falls below the minimumspecified operating voltage.




Fig 5. Block diagram of oscillator control.

÷2

002aaa424

RTC

CPU

WDT

BAUD RATEGENERATOR

DIVMCCLK

UART

OSCCLK

I2C

PCLK

TIMER 0 andTIMER 1

High freq.Med. freq.Low freq.

XTAL1

XTAL2

RCOSCILLATOR

WATCHDOGOSCILLATOR

(7.3728 MHz)

(400 kHz)




8.6 CPU Clock (CCLK) wake-up delayThe P89LPC920/921/922/9221 has an internal wake-up timer that delays the clockuntil it stabilizes depending to the clock source used. If the clock source is any of thethree crystal selections (low, medium and high frequencies) the delay is992 OSCCLK cycles plus 60 to 100 µs. If the clock source is either the internal RCoscillator, watchdog oscillator, or external clock, the delay is 224 OSCCLK cycles plus60 to 100 µs.

8.7 CPU Clock (CCLK) modification: DIVM registerThe OSCCLK frequency can be divided down up to 510 times by configuring adividing register, DIVM, to generate CCLK. This feature makes it possible totemporarily run the CPU at a lower rate, reducing power consumption. By dividing theclock, the CPU can retain the ability to respond to events that would not exit Idlemode by executing its normal program at a lower rate. This can also allow bypassingthe oscillator start-up time in cases where Power-down mode would otherwise beused. The value of DIVM may be changed by the program at any time withoutinterrupting code execution.

8.8 Low power selectThe P89LPC920/921/922/9221 is designed to run at 18 MHz (CCLK) maximum.However, if CCLK is 8 MHz or slower, the CLKLP SFR bit (AUXR1.7) can be set to ‘1’to lower the power consumption further. On any reset, CLKLP is ‘0’ allowing highestperformance access. This bit can then be set in software if CCLK is running at 8 MHzor slower.

8.9 Memory organizationThe various P89LPC920/921/922/9221 memory spaces are as follows:

• DATA

128 bytes of internal data memory space (00h:7Fh) accessed via direct or indirectaddressing, using instruction other than MOVX and MOVC. All or part of the Stackmay be in this area.

• IDATA

Indirect Data. 256 bytes of internal data memory space (00h:FFh) accessed viaindirect addressing using instructions other than MOVX and MOVC. All or part ofthe Stack may be in this area. This area includes the DATA area and the 128 bytesimmediately above it.

• SFR

Special Function Registers. Selected CPU registers and peripheral control andstatus registers, accessible only via direct addressing.

• CODE

64 kB of Code memory space, accessed as part of program execution and via theMOVC instruction. The P89LPC920/921/922/9221 has 2 kB/4 kB/8 kB of on-chipCode memory.




8.10 Data RAM arrangementThe 256 bytes of on-chip RAM are organized as shown in Table 5.

8.11 InterruptsThe P89LPC920/921/922/9221 uses a four priority level interrupt structure. Thisallows great flexibility in controlling the handling of the many interrupt sources. TheP89LPC920/921/922/9221 supports 12 interrupt sources: external interrupts 0 and 1,timers 0 and 1, serial port Tx, serial port Rx, combined serial port Rx/Tx, brownoutdetect, watchdog/real-time clock, I2C, keyboard, and comparators 1 and 2.

Each interrupt source can be individually enabled or disabled by setting or clearing abit in the interrupt enable registers IEN0 or IEN1. The IEN0 register also contains aglobal disable bit, EA, which disables all interrupts.

Each interrupt source can be individually programmed to one of four priority levels bysetting or clearing bits in the interrupt priority registers IP0, IP0H, IP1, and IP1H. Aninterrupt service routine in progress can be interrupted by a higher priority interrupt,but not by another interrupt of the same or lower priority. The highest priority interruptservice cannot be interrupted by any other interrupt source. If two requests ofdifferent priority levels are pending at the start of an instruction, the request of higherpriority level is serviced.

If requests of the same priority level are pending at the start of an instruction, aninternal polling sequence determines which request is serviced. This is called thearbitration ranking. Note that the arbitration ranking is only used to resolve pendingrequests of the same priority level.

8.11.1 External interrupt inputs

The P89LPC920/921/922/9221 has two external interrupt inputs as well as theKeypad Interrupt function. The two interrupt inputs are identical to those present onthe standard 80C51 microcontrollers.

These external interrupts can be programmed to be level-triggered or edge-triggeredby setting or clearing bit IT1 or IT0 in Register TCON.

In edge-triggered mode if successive samples of the INTn pin show a HIGH in onecycle and a LOW in the next cycle, the interrupt request flag IEn in TCON is set,causing an interrupt request.

If an external interrupt is enabled when the P89LPC920/921/922/9221 is put intoPower-down or Idle mode, the interrupt will cause the processor to wake-up andresume operation. Refer to Section 8.14 “Power reduction modes” for details.

Table 5: On-chip data memory usages

Type Data RAM Size (bytes)

DATA Memory that can be addressed directly and indirectly 128

IDATA Memory that can be addressed indirectly 256




8.12 I/O portsThe P89LPC920/921/922/9221 has three I/O ports: Port 0, Port 1, and Port 3. Ports 0and 1 are 8-bit ports, and Port 3 is a 2-bit port. The exact number of I/O pins availabledepend upon the clock and reset options chosen, as shown in Table 6.

[1] Required for operation above 12 MHz.

8.12.1 Port configurations

All but three I/O port pins on the P89LPC920/921/922/9221 may be configured bysoftware to one of four types on a bit-by-bit basis. These are: quasi-bidirectional(standard 80C51 port outputs), push-pull, open drain, and input-only. Twoconfiguration registers for each port select the output type for each port pin.

P1.5 (RST) can only be an input and cannot be configured.

Fig 6. Interrupt sources, interrupt enables, and power-down wake-up sources.

002aaa418

IE0EX0

IE1EX1

BOFEBO

KBIFEKBI

INTERRUPT TO CPU

WAKE-UP(IF IN POWER-DOWN)

EWDRTCMF2CMF1

EC

EA (IE0.7)

TF0ET0

TF1ET1

TI & RI/RIES/ESR

TIEST

SIEI2C

RTCFERTC

(RTCCON.1)

WDOVF

Table 6: Number of I/O pins available

Clock source Reset option Number of I/O pins(20-pin package)

On-chip oscillator orwatchdog oscillator

No external reset (except during power-up) 18

External RST pin supported[1] 17

External clock input No external reset (except during power-up) 17


Low/medium/highspeed oscillator(external crystal orresonator)

No external reset (except during power-up) 16





P1.2 (SCL/T0) and P1.3 (SDA/INT0) may only be configured to be either input-only oropen-drain.

8.12.2 Quasi-bidirectional output configuration

Quasi-bidirectional output type can be used as both an input and output without theneed to reconfigure the port. This is possible because when the port outputs a logicHIGH, it is weakly driven, allowing an external device to pull the pin LOW. When thepin is driven LOW, it is driven strongly and able to sink a fairly large current. Thesefeatures are somewhat similar to an open-drain output except that there are threepull-up transistors in the quasi-bidirectional output that serve different purposes.

The P89LPC920/921/922/9221 is a 3 V device, but the pins are 5 V-tolerant. Inquasi-bidirectional mode, if a user applies 5 V on the pin, there will be a currentflowing from the pin to VDD, causing extra power consumption. Therefore, applying5 V in quasi-bidirectional mode is discouraged.

A quasi-bidirectional port pin has a Schmitt-triggered input that also has a glitchsuppression circuit.

8.12.3 Open-drain output configuration

The open-drain output configuration turns off all pull-ups and only drives thepull-down transistor of the port driver when the port latch contains a logic ‘0’. To beused as a logic output, a port configured in this manner must have an externalpull-up, typically a resistor tied to VDD.

An open-drain port pin has a Schmitt-triggered input that also has a glitchsuppression circuit.

8.12.4 Input-only configuration

The input-only port configuration has no output drivers. It is a Schmitt-triggered inputthat also has a glitch suppression circuit.

8.12.5 Push-pull output configuration

The push-pull output configuration has the same pull-down structure as both theopen-drain and the quasi-bidirectional output modes, but provides a continuousstrong pull-up when the port latch contains a logic ‘1’. The push-pull mode may beused when more source current is needed from a port output. A push-pull port pinhas a Schmitt-triggered input that also has a glitch suppression circuit. TheP89LPC9221 device has high source current on eight pins in push-pull mode. SeeTable 8 “DC electrical characteristics”.

8.12.6 Port 0 analog functions

The P89LPC920/921/922/9221 incorporates two Analog Comparators. In order togive the best analog function performance and to minimize power consumption, pinsthat are being used for analog functions must have the digital outputs and digitalinputs disabled.

Digital outputs are disabled by putting the port output into the Input-Only (highimpedance) mode as described in Section 8.12.4.

Digital inputs on Port 0 may be disabled through the use of the PT0AD register,bits 1:5. On any reset, PT0AD1:5 defaults to ‘0’s to enable digital functions.




8.12.7 Additional port features

After power-up, all pins are in Input-Only mode. Please note that this is differentfrom the LPC76x series of devices.

• After power-up, all I/O pins except P1.5, may be configured by software.

• Pin P1.5 is input only. Pins P1.2 and P1.3 and are configurable for either input-onlyor open-drain.

Every output on the P89LPC920/921/922/9221 has been designed to sink typicalLED drive current. However, there is a maximum total output current for all portswhich must not be exceeded. Please refer to Table 8 “DC electrical characteristics” fordetailed specifications.

All ports pins that can function as an output have slew rate controlled outputs to limitnoise generated by quickly switching output signals. The slew rate is factory-set toapproximately 10 ns rise and fall times.

8.13 Power monitoring functionsThe P89LPC920/921/922/9221 incorporates power monitoring functions designed toprevent incorrect operation during initial power-up and power loss or reduction duringoperation. This is accomplished with two hardware functions: Power-on Detect andBrownout detect.

8.13.1 Brownout detection

The Brownout detect function determines if the power supply voltage drops below acertain level. The default operation is for a Brownout detection to cause a processorreset, however it may alternatively be configured to generate an interrupt.

Brownout detection may be enabled or disabled in software.

If Brownout detection is enabled, the brownout condition occurs when VDD falls belowthe brownout trip voltage, VBO (see Table 8 “DC electrical characteristics”), and isnegated when VDD rises above VBO. If the P89LPC920/921/922/9221 device is tooperate with a power supply that can be below 2.7 V, BOE should be left in theunprogrammed state so that the device can operate at 2.4 V, otherwise continuousbrownout reset may prevent the device from operating.

For correct activation of Brownout detect, the VDD rise and fall times must beobserved. Please see Table 8 “DC electrical characteristics” for specifications.

8.13.2 Power-on detection

The Power-on Detect has a function similar to the Brownout detect, but is designed towork as power comes up initially, before the power supply voltage reaches a levelwhere Brownout detect can work. The POF flag in the RSTSRC register is set toindicate an initial power-up condition. The POF flag will remain set until cleared bysoftware.

8.14 Power reduction modesThe P89LPC920/921/922/9221 supports three different power reduction modes.These modes are Idle mode, Power-down mode, and total Power-down mode.




8.14.1 Idle mode

Idle mode leaves peripherals running in order to allow them to activate the processorwhen an interrupt is generated. Any enabled interrupt source or reset may terminateIdle mode.

8.14.2 Power-down mode

The Power-down mode stops the oscillator in order to minimize power consumption.The P89LPC920/921/922/9221 exits Power-down mode via any reset, or certaininterrupts. In Power-down mode, the power supply voltage may be reduced to theRAM keep-alive voltage VRAM. This retains the RAM contents at the point wherePower-down mode was entered. SFR contents are not guaranteed after VDD hasbeen lowered to VRAM, therefore it is highly recommended to wake up the processorvia reset in this case. VDD must be raised to within the operating range before thePower-down mode is exited.

Some chip functions continue to operate and draw power during Power-down mode,increasing the total power used during Power-down. These include: Brownout detect,Watchdog Timer, Comparators (note that Comparators can be powered-downseparately), and Real-Time Clock (RTC)/System Timer. The internal RC oscillator isdisabled unless both the RC oscillator has been selected as the system clock ANDthe RTC is enabled.

8.14.3 Total Power-down mode

This is the same as Power-down mode except that the brownout detection circuitryand the voltage comparators are also disabled to conserve additional power. Theinternal RC oscillator is disabled unless both the RC oscillator has been selected asthe system clock and the RTC is enabled. If the internal RC oscillator is used to clockthe RTC during Power-down, there will be high power consumption. Please use anexternal low frequency clock to achieve low power with the Real-Time Clock runningduring Power-down.

8.15 ResetThe P1.5/RST pin can function as either an active-LOW reset input or as a digitalinput, P1.5. The RPE (Reset Pin Enable) bit in UCFG1, when set to ‘1’, enables theexternal reset input function on P1.5. When cleared, P1.5 may be used as an inputpin.

Remark: During a power-up sequence, the RPE selection is overridden and this pinwill always function as a reset input. An external circuit connected to this pinshould not hold this pin LOW during a power-on sequence as this will keep thedevice in reset. After power-up this input will function either as an external resetinput or as a digital input as defined by the RPE bit. Only a power-up reset willtemporarily override the selection defined by RPE bit. Other sources of reset will notoverride the RPE bit.

Remark: During a power cycle, VDD must fall below VPOR (see Table 8 “DC electricalcharacteristics” on page 36) before power is reapplied, in order to ensure a power-onreset.

Reset can be triggered from the following sources:




• External reset pin (during power-up or if user configured via UCFG1). This optionmust be used for an oscillator frequency above 12 MHz);

• Power-on detect;

• Brownout detect;

• Watchdog Timer;

• Software reset;

• UART break character detect reset.

For every reset source, there is a flag in the Reset Register, RSTSRC. The user canread this register to determine the most recent reset source. These flag bits can becleared in software by writing a ‘0’ to the corresponding bit. More than one flag bitmay be set:

• During a power-on reset, both POF and BOF are set but the other flag bits arecleared.

• For any other reset, previously set flag bits that have not been cleared will remainset.

8.15.1 Reset vector

Following reset, the P89LPC920/921/922/9221 will fetch instructions from eitheraddress 0000h or the Boot address. The Boot address is formed by using the BootVector as the high byte of the address and the low byte of the address = 00h.

The Boot address will be used if a UART break reset occurs, or the non-volatile BootStatus bit (BOOTSTAT.0) = 1, or the device is forced into ISP mode during power-on(see P89LPC920/921/922/9221 User’s Manual). Otherwise, instructions will befetched from address 0000H.

8.16 Timers/counters 0 and 1The P89LPC920/921/922/9221 has two general purpose counter/timers which areupward compatible with the standard 80C51 Timer 0 and Timer 1. Both can beconfigured to operate either as timers or event counter. An option to automaticallytoggle the T0 and/or T1 pins upon timer overflow has been added.

In the ‘Timer’ function, the register is incremented every machine cycle.

In the ‘Counter’ function, the register is incremented in response to a 1-to-0 transitionat its corresponding external input pin, T0 or T1. In this function, the external input issampled once during every machine cycle.

Timer 0 and Timer 1 have five operating modes (modes 0, 1, 2, 3 and 6). Modes 0, 1,2 and 6 are the same for both Timers/Counters. Mode 3 is different.

8.16.1 Mode 0

Putting either Timer into Mode 0 makes it look like an 8048 Timer, which is an 8-bitCounter with a divide-by-32 prescaler. In this mode, the Timer register is configuredas a 13-bit register. Mode 0 operation is the same for Timer 0 and Timer 1.

8.16.2 Mode 1

Mode 1 is the same as Mode 0, except that all 16 bits of the timer register are used.




8.16.3 Mode 2

Mode 2 configures the Timer register as an 8-bit Counter with automatic reload.Mode 2 operation is the same for Timer 0 and Timer 1.

8.16.4 Mode 3

When Timer 1 is in Mode 3 it is stopped. Timer 0 in Mode 3 forms two separate 8-bitcounters and is provided for applications that require an extra 8-bit timer. WhenTimer 1 is in Mode 3 it can still be used by the serial port as a baud rate generator.

8.16.5 Mode 6

In this mode, the corresponding timer can be changed to a PWM with a full period of256 timer clocks.

8.16.6 Timer overflow toggle output

Timers 0 and 1 can be configured to automatically toggle a port output whenever atimer overflow occurs. The same device pins that are used for the T0 and T1 countinputs are also used for the timer toggle outputs. The port outputs will be a logic 1prior to the first timer overflow when this mode is turned on.

8.17 Real-Time clock/system timerThe P89LPC920/921/922/9221 has a simple Real-Time clock that allows a user tocontinue running an accurate timer while the rest of the device is powered-down. TheReal-Time clock can be a wake-up or an interrupt source. The Real-Time clock is a23-bit down counter comprised of a 7-bit prescaler and a 16-bit loadable downcounter. When it reaches all ‘0’s, the counter will be reloaded again and the RTCFflag will be set. The clock source for this counter can be either the CPU clock (CCLK)or the XTAL oscillator, provided that the XTAL oscillator is not being used as the CPUclock. If the XTAL oscillator is used as the CPU clock, then the RTC will use CCLK asits clock source. Only power-on reset will reset the Real-Time clock and itsassociated SFRs to the default state.

8.18 UARTThe P89LPC920/921/922/9221 has an enhanced UART that is compatible with theconventional 80C51 UART except that Timer 2 overflow cannot be used as a baudrate source. The P89LPC920/921/922/9221 does include an independent Baud RateGenerator. The baud rate can be selected from the oscillator (divided by a constant),Timer 1 overflow, or the independent Baud Rate Generator. In addition to the baudrate generation, enhancements over the standard 80C51 UART include FramingError detection, automatic address recognition, selectable double buffering andseveral interrupt options.The UART can be operated in 4 modes: shift register, 8-bitUART, 9-bit UART, and CPU clock/32 or CPU clock/16.

8.18.1 Mode 0

Serial data enters and exits through RxD. TxD outputs the shift clock. 8 bits aretransmitted or received, LSB first. The baud rate is fixed at 1⁄16 of the CPU clockfrequency.




8.18.2 Mode 1

10 bits are transmitted (through TxD) or received (through RxD): a start bit(logical ‘0’), 8 data bits (LSB first), and a stop bit (logical ‘1’). When data is received,the stop bit is stored in RB8 in Special Function Register SCON. The baud rate isvariable and is determined by the Timer 1 overflow rate or the Baud Rate Generator(described in Section 8.18.5 “Baud rate generator and selection”).

8.18.3 Mode 2

11 bits are transmitted (through TxD) or received (through RxD): start bit (logical ‘0’),8 data bits (LSB first), a programmable 9th data bit, and a stop bit (logical ‘1’). Whendata is transmitted, the 9th data bit (TB8 in SCON) can be assigned the value of ‘0’ or‘1’. Or, for example, the parity bit (P, in the PSW) could be moved into TB8. Whendata is received, the 9th data bit goes into RB8 in Special Function Register SCON,while the stop bit is not saved. The baud rate is programmable to either 1⁄16 or 1⁄32 ofthe CPU clock frequency, as determined by the SMOD1 bit in PCON.

8.18.4 Mode 3

11 bits are transmitted (through TxD) or received (through RxD): a start bit(logical ‘0’), 8 data bits (LSB first), a programmable 9th data bit, and a stop bit(logical ‘1’). In fact, Mode 3 is the same as Mode 2 in all respects except baud rate.The baud rate in Mode 3 is variable and is determined by the Timer 1 overflow rate orthe Baud Rate Generator (described in Section 8.18.5 “Baud rate generator andselection”).

8.18.5 Baud rate generator and selection

The P89LPC920/921/922/9221 enhanced UART has an independent Baud RateGenerator. The baud rate is determined by a baud-rate preprogrammed into theBRGR1 and BRGR0 SFRs which together form a 16-bit baud rate divisor value thatworks in a similar manner as Timer 1 but is much more accurate. If the baud rategenerator is used, Timer 1 can be used for other timing functions.

The UART can use either Timer 1 or the baud rate generator output (see Figure 7).Note that Timer T1 is further divided by 2 if the SMOD1 bit (PCON.7) is set. Theindependent Baud Rate Generator uses OSCCLK.

8.18.6 Framing error

Framing error is reported in the status register (SSTAT). In addition, if SMOD0(PCON.6) is ‘1’, framing errors can be made available in SCON.7 respectively. IfSMOD0 is ‘0’, SCON.7 is SM0. It is recommended that SM0 and SM1 (SCON.7:6)are set up when SMOD0 is ‘0’.

Fig 7. Baud rate sources for UART (Modes 1, 3).

Baud Rate Modes 1 and 3

SBRGS = 1

SBRGS = 0

SMOD1 = 0

SMOD1 = 1

¸2

Timer 1 Overflow(PCLK-based)

Baud Rate Generator(CCLK-based)

002aaa419




8.18.7 Break detect

Break detect is reported in the status register (SSTAT). A break is detected when11 consecutive bits are sensed LOW. The break detect can be used to reset thedevice and force the device into ISP mode.

8.18.8 Double buffering

The UART has a transmit double buffer that allows buffering of the next character tobe written to SBUF while the first character is being transmitted. Double bufferingallows transmission of a string of characters with only one stop bit between any twocharacters, as long as the next character is written between the start bit and the stopbit of the previous character.

Double buffering can be disabled. If disabled (DBMOD, i.e., SSTAT.7 = ‘0’), the UARTis compatible with the conventional 80C51 UART. If enabled, the UART allows writingto SnBUF while the previous data is being shifted out. Double buffering is onlyallowed in Modes 1, 2 and 3. When operated in Mode 0, double buffering must bedisabled (DBMOD = ‘0’).

8.18.9 Transmit interrupts with double buffering enabled (Modes 1, 2 and 3)

Unlike the conventional UART, in double buffering mode, the Tx interrupt is generatedwhen the double buffer is ready to receive new data.

8.18.10 The 9th bit (bit 8) in double buffering (Modes 1, 2 and 3)

If double buffering is disabled TB8 can be written before or after SBUF is written, aslong as TB8 is updated some time before that bit is shifted out. TB8 must not bechanged until the bit is shifted out, as indicated by the Tx interrupt.

If double buffering is enabled, TB8 must be updated before SBUF is written, as TB8will be double-buffered together with SBUF data.




8.19 I2C-bus serial interfaceI2C-bus uses two wires (SDA and SCL) to transfer information between devicesconnected to the bus, and it has the following features:

• Bidirectional data transfer between masters and slaves

• Multimaster bus (no central master)

• Arbitration between simultaneously transmitting masters without corruption ofserial data on the bus

• Serial clock synchronization allows devices with different bit rates to communicatevia one serial bus

• Serial clock synchronization can be used as a handshake mechanism to suspendand resume serial transfer

• The I2C-bus may be used for test and diagnostic purposes.

A typical I2C-bus configuration is shown in Figure 8. The P89LPC920/921/922/9221device provides a byte-oriented I2C-bus interface that supports data transfers up to400 kHz.

Fig 8. I2C-bus configuration.

OTHER DEVICEWITH I2C-BUS

INTERFACE

SDA

SCL

RPRP

OTHER DEVICEWITH I2C-BUS

INTERFACE

P1.3/SDA P1.2/SCL

P89LPC920/921/922

I2C-BUS

002aaa420




Fig 9. I2C-bus serial interface block diagram.

INT

ER

NA

L B

US

002aaa421

ADDRESS REGISTER

COMPARATOR

SHIFT REGISTER

8

I2ADR

ACK

BIT COUNTER /ARBITRATION &

SYNC LOGIC

8 I2DAT

TIMING&

CONTROLLOGIC

SERIAL CLOCKGENERATOR

CCLK

INTERRUPT

INPUTFILTER

OUTPUTSTAGE

INPUTFILTER

OUTPUTSTAGE

P1.3

P1.3/SDA

P1.2/SCL

P1.2

TIMER 1OVERFLOW

CONTROL REGISTERS &SCL DUTY CYCLE REGISTERS

I2CONI2SCLHI2SCLL

8

STATUSDECODERSTATUS BUS

STATUS REGISTER

8

I2STAT




8.20 Analog comparatorsTwo analog comparators are provided on the P89LPC920/921/922/9221. Input andoutput options allow use of the comparators in a number of different configurations.Comparator operation is such that the output is a logical one (which may be read in aregister and/or routed to a pin) when the positive input (one of two selectable pins) isgreater than the negative input (selectable from a pin or an internal referencevoltage). Otherwise the output is a zero. Each comparator may be configured tocause an interrupt when the output value changes.

The overall connections to both comparators are shown in Figure 10. Thecomparators function to VDD = 2.4 V.

When each comparator is first enabled, the comparator output and interrupt flag arenot guaranteed to be stable for 10 microseconds. The corresponding comparatorinterrupt should not be enabled during that time, and the comparator interrupt flagmust be cleared before the interrupt is enabled in order to prevent an immediateinterrupt service.

When a comparator is disabled the comparator’s output, COx, goes HIGH. If thecomparator output was LOW and then is disabled, the resulting transition of thecomparator output from a LOW to HIGH state will set the comparator flag, CMFx.This will cause an interrupt if the comparator interrupt is enabled. The user shouldtherefore disable the comparator interrupt prior to disabling the comparator.Additionally, the user should clear the comparator flag, CMFx, after disabling thecomparator.

8.20.1 Internal reference voltage

An internal reference voltage generator may supply a default reference when a singlecomparator input pin is used. The value of the internal reference voltage, referred toas VREF, is 1.23 V ±10%.

Fig 10. Comparator input and output connections.

Comparator 1CP1

CN1

(P0.4) CIN1A

(P0.3) CIN1B

(P0.5) CMPREF

VREF

OE1

Change Detect

CO1

CMF1

Interrupt

002aaa422

CMP1 (P0.6)

ECChange Detect

CMF2Comparator 2

OE2

CO2CMP2 (P0.0)

CP2

CN2

(P0.2) CIN2A

(P0.1) CIN2B




8.20.2 Comparator interrupt

Each comparator has an interrupt flag contained in its configuration register. This flagis set whenever the comparator output changes state. The flag may be polled bysoftware or may be used to generate an interrupt. The two comparators use onecommon interrupt vector. If both comparators enable interrupts, after entering theinterrupt service routine, the user needs to read the flags to determine whichcomparator caused the interrupt.

8.20.3 Comparators and power reduction modes

Either or both comparators may remain enabled when Power-down or Idle mode isactivated, but both comparators are disabled automatically in Total Power-downmode. If a comparator interrupt is enabled (except in Total Power-down mode), achange of the comparator output state will generate an interrupt and wake up theprocessor. If the comparator output to a pin is enabled, the pin should be configuredin the push-pull mode in order to obtain fast switching times while in Power-downmode. The reason is that with the oscillator stopped, the temporary strong pull-up thatnormally occurs during switching on a quasi-bidirectional port pin does not takeplace.

Comparators consume power in Power-down and Idle modes, as well as in thenormal operating mode. This fact should be taken into account when system powerconsumption is an issue. To minimize power consumption, the user can disable thecomparators via PCONA.5, or put the device in Total Power-down mode.

8.21 Keypad interrupt (KBI)The Keypad Interrupt function is intended primarily to allow a single interrupt to begenerated when Port 0 is equal to or not equal to a certain pattern. This function canbe used for bus address recognition or keypad recognition. The user can configurethe port via SFRs for different tasks.

The Keypad Interrupt Mask Register (KBMASK) is used to define which input pinsconnected to Port 0 can trigger the interrupt. The Keypad Pattern Register (KBPATN)is used to define a pattern that is compared to the value of Port 0. The KeypadInterrupt Flag (KBIF) in the Keypad Interrupt Control Register (KBCON) is set whenthe condition is matched while the Keypad Interrupt function is active. An interrupt willbe generated if enabled. The PATN_SEL bit in the Keypad Interrupt Control Register(KBCON) is used to define equal or not-equal for the comparison.

In order to use the Keypad Interrupt as an original KBI function like in 87LPC76xseries, the user needs to set KBPATN = 0FFH and PATN_SEL = 1 (not equal), thenany key connected to Port 0 which is enabled by the KBMASK register will cause thehardware to set KBIF and generate an interrupt if it has been enabled. The interruptmay be used to wake up the CPU from Idle or Power-down modes. This feature isparticularly useful in handheld, battery-powered systems that need to carefullymanage power consumption yet also need to be convenient to use.

In order to set the flag and cause an interrupt, the pattern on Port 0 must be heldlonger than 6 CCLKs.




8.22 Watchdog timerThe Watchdog timer causes a system reset when it underflows as a result of a failureto feed the timer prior to the timer reaching its terminal count. It consists of aprogrammable 12-bit prescaler, and an 8-bit down counter. The down counter isdecremented by a tap taken from the prescaler. The clock source for the prescaler iseither the PCLK or the nominal 400 kHz Watchdog oscillator. The Watchdog timercan only be reset by a power-on reset. When the watchdog feature is disabled, it canbe used as an interval timer and may generate an interrupt. Figure 11 shows theWatchdog timer in watchdog mode. Feeding the watchdog requires a two-bytesequence. If PCLK is selected as the watchdog clock and the CPU is powered-down,the watchdog is disabled. The Watchdog timer has a time-out period that ranges froma few µs to a few seconds. Please refer to the P89LPC920/921/922/9221 User’sManual for more details.

8.23 Additional features

8.23.1 Software reset

The SRST bit in AUXR1 gives software the opportunity to reset the processorcompletely, as if an external reset or watchdog reset had occurred. Care should betaken when writing to AUXR1 to avoid accidental software resets.

8.23.2 Dual data pointers

The dual Data Pointers (DPTR) provides two different Data Pointers to specify theaddress used with certain instructions. The DPS bit in the AUXR1 register selectsone of the two Data Pointers. Bit 2 of AUXR1 is permanently wired as a logic ‘0’ sothat the DPS bit may be toggled (thereby switching Data Pointers) simply byincrementing the AUXR1 register, without the possibility of inadvertently altering otherbits in the register.

(1) Watchdog reset can also be caused by an invalid feed sequence, or by writing to WDCON not immediately followed by afeed sequence.

Fig 11. Watchdog timer in watchdog mode (WDTE = ‘1’).

PRE2 PRE1 PRE0 – – WDRUN WDTOF WDCLKWDCON (A7H)

CONTROL REGISTER

PRESCALER

002aaa423

SHADOW REGISTERFOR WDCON

8-BIT DOWN COUNTER

WDL (C1H)

Watchdogoscillator

PCLK÷32

MOV WFEED1, #0A5HMOV WFEED2, #05AH

RESETsee note (1)




8.24 Flash program memory

8.24.1 General description

The P89LPC920/921/922/9221 Flash memory provides in-circuit electrical erasureand programming. The Flash can be read, erased, or written as bytes. The Sectorand Page Erase functions can erase any Flash sector (1 kB) or page (64 bytes). TheChip Erase operation will erase the entire program memory. In-System Programmingand standard parallel programming are both available. On-chip erase and write timinggeneration contribute to a user-friendly programming interface. TheP89LPC920/921/922/9221 Flash reliably stores memory contents even after10,000 erase and program cycles. The cell is designed to optimize the erase andprogramming mechanisms. The P89LPC920/921/922/9221 uses VDD as the supplyvoltage to perform the Program/Erase algorithms.

8.24.2 Features

• Parallel programming with industry-standard commercial programmers.

• In-Circuit serial Programming (ICP) with industry-standard commercialprogrammers.

• IAP-Lite allows individual and multiple bytes of code memory to be used for datastorage and programmed under control of the end application.

• Internal fixed boot ROM, containing low-level In-Application Programming (IAP)routines that can be called from the end application (in addition to IAP-Lite).

• Default serial loader providing In-System Programming (ISP) via the serial port,located in upper end of user program memory.

• Boot vector allows user-provided Flash loader code to reside anywhere in theFlash memory space, providing flexibility to the user.

• Programming and erase over the full operating voltage range.

• Read/Programming/Erase using ISP/IAP/IAP-Lite.

• Any flash program or erase operation in 2 ms.

• Programmable security for the code in the Flash for each sector.

• >100,000 typical erase/program cycles for each byte.

• 10 year minimum data retention.

8.24.3 ISP and IAP capabilities of the P89LPC920/921/922/9221

Flash organization: The P89LPC920/921/922/9221 program memory consists oftwo/four/eight 1 kB sectors. Each sector can be further divided into 64-byte pages. Inaddition to sector erase, page erase, and byte erase, a 64-byte page register isincluded which allows from 1 to 64 bytes of a given page to be programmed at thesame time, substantially reducing overall programming time. An In-ApplicationProgramming (IAP) interface is provided to allow the end user’s application to eraseand reprogram the user code memory. In addition, erasing and reprogramming ofuser-programmable bytes including UCFG1, the Boot Status Bit and the Boot Vectorare supported. As shipped from the factory, the upper 512 bytes of user code spacecontains a serial In-System Programming (ISP) routine allowing for the device to beprogrammed in circuit through the serial port.




Flash programming and erasing: There are three methods of erasing orprogramming of the Flash memory that may be used. First, the Flash may beprogrammed or erased in the end-user application by calling low-level routinesthrough a common entry point. Second, the on-chip ISP boot loader may be invoked.This ISP boot loader will, in turn, call low-level routines through the same commonentry point that can be used by the end-user application. Third, the Flash may beprogrammed or erased using the parallel method by using a commercially availableEPROM programmer which supports this device. This device does not provide fordirect verification of code memory contents. Instead this device provides a 32-bitCRC result on either a sector or the entire 2 kB/4 kB/8 kB of user code space.

Boot ROM: When the microcontroller programs its own Flash memory, all of thelow-level details are handled by code that is contained in a Boot ROM that is separatefrom the Flash memory. A user program simply calls the common entry point in theBoot ROM with appropriate parameters to accomplish the desired operation. TheBoot ROM include operations such as erase sector, erase page, program page, CRC,program security bit, etc. The Boot ROM occupies the program memory space at thetop of the address space from FF00H to FEFFH, thereby not conflicting with the userprogram memory space.

Power-on reset code execution: The P89LPC920/921/922/9221 contains twospecial Flash elements: the Boot Vector and the Boot Status Bit. Following reset, theP89LPC920/921/922/9221 examines the contents of the Boot Status Bit. If the BootStatus Bit is set to zero, power-up execution starts at location 0000H, which is thenormal start address of the user’s application code. When the Boot Status Bit is set toa one, the contents of the Boot Vector is used as the high byte of the executionaddress and the low byte is set to 00H. The factory default setting is 1FH for theP89LPC9221 and P89LPC922, and corresponds to the address 1F00H for the defaultISP boot loader. The factory default setting is 0FH for the P89LPC921 andcorresponds to the address 0F00H for the default ISP boot loader. The factory defaultsetting for the LPC920 is 07H and corresponds to the address 0700H. This bootloader is pre-programmed at the factory into this address space and can be erasedby the user. Users who wish to use this loader should take precautions to avoiderasing the 1 kB sector from 1C00H to 1FFFH in the P89LPC922/9221 or the1 kB sector from 0C00H to 0FFFH in the P89LPC921, or the 1 kB sector from0400H to 07FFH in the P89LPC920. Instead, the page erase function can beused to erase the eight 64-byte pages which comprise the lower 512 bytes ofthe sector. A custom boot loader can be written with the Boot Vector set to thecustom boot loader, if desired.

Hardware activation of the boot loader: The boot loader can also be executed byforcing the device into ISP mode during a power-on sequence (see theP89LPC920/921/922/9221 User’s Manual for specific information). This has the sameeffect as having a non-zero Boot Status Bit. This allows an application to be built thatwill normally execute user code but can be manually forced into ISP operation. If thefactory default setting for the Boot Vector is changed, it will no longer point to thefactory pre-programmed ISP boot loader code. If this happens, the only way it ispossible to change the contents of the Boot Vector is through the parallelprogramming method, provided that the end user application does not contain acustomized loader that provides for erasing and reprogramming of the Boot Vector




and Boot Status Bit. After programming the Flash, the Boot Status Bit should beprogrammed to zero in order to allow execution of the user’s application codebeginning at address 0000H.

In-System Programming (ISP): In-System Programming is performed withoutremoving the microcontroller from the system. The In-System Programming facilityconsists of a series of internal hardware resources coupled with internal firmware tofacilitate remote programming of the P89LPC920/921/922/9221 through the serialport. This firmware is provided by Philips and embedded within eachP89LPC920/921/922/9221 device. The Philips In-System Programming facility hasmade in-system programming in an embedded application possible with a minimumof additional expense in components and circuit board area. The ISP function usesfive pins (VDD, VSS, TXD, RXD, and RST). Only a small connector needs to beavailable to interface your application to an external circuit in order to use this feature.Please see the P89LPC920/921/922/9221 User’s Manual for additional details.

In-Application Programming (IAP): Several In-Application Programming (IAP) callsare available for use by an application program to permit selective erasing andprogramming of Flash sectors, pages, security bits, configuration bytes, and deviceidentification. All calls are made through a common interface, PGM_MTP. Theprogramming functions are selected by setting up the microcontroller’s registersbefore making a call to PGM_MTP at FF00H. Please see theP89LPC920/921/922/9221 User’s Manual for additional details.

In-Circuit Programming (ICP): In-Circuit Programming is a method intended toallow commercial programmers to program and erase these devices withoutremoving the microcontroller from the system. The In-Circuit Programming facilityconsists of a series of internal hardware resources to facilitate remote programmingof the P89LPC920/921/922/9221 through a two-wire serial interface. Philips hasmade in-circuit programming in an embedded application possible with a minimum ofadditional expense in components and circuit board area. The ICP function uses fivepins (VDD, VSS, P0.5, P0.4, and RST). Only a small connector needs to be availableto interface your application to an external programmer in order to use this feature.

8.25 User configuration bytesA number of user-configurable features of the P89LPC920/921/922/9221 must bedefined at power-up and therefore cannot be set by the program after start ofexecution. These features are configured through the use of the Flash byte UCFG1.Please see the P89LPC920/921/922/9221 User’s Manual for additional details.

8.26 User sector security bytesThere are two/four/eight User Sector Security Bytes, each corresponding to onesector. Please see the P89LPC920/921/922/9221 User’s Manual for additionaldetails.




9. Limiting values

[1] The following applies to Limiting values:

a) Stresses above those listed under Table 7 may cause permanent damage to the device. This is a stress rating only and functionaloperation of the device at these or any conditions other than those described in Table 8 “DC electrical characteristics”, Table 9 “ACcharacteristics” and Table 10 “AC characteristics” of this specification are not implied.

b) This product includes circuitry specifically designed for the protection of its internal devices from the damaging effects of excessivestatic charge. Nonetheless, it is suggested that conventional precautions be taken to avoid applying greater than the rated maximum.

c) Parameters are valid over operating temperature range unless otherwise specified. All voltages are with respect to VSS unlessotherwise noted.

Table 7: Limiting values [1]

In accordance with the Absolute Maximum Rating System (IEC 60134).

Symbol Parameter Conditions Min Max Unit

Tamb(bias) operating bias ambient temperature −55 +125 °C

Tstg storage temperature range −65 +150 °C

Vxtal voltage on XTAL1, XTAL2 pin to VSS - VDD + 0.5 V

Vn voltage on any other pin to VSS −0.5 +5.5 V

IOH(I/O) HIGH-level output current per I/O pin,P89LPC9221

P0.3 to P0.7, P1.4, P1.6,P1.7

- 20 mA

all other I/O pins - 8 mA

HIGH-level output current per I/O pin,P89LPC920/921/922

- 8 mA

IOL(I/O) LOW-level output current per I/O pin - 20 mA

II/O(tot)(max) maximum total I/O current,P89LPC9221

- 160 mA

maximum total I/O current,P89LPC920/921/922

- 80 mA

Ptot(pack) total power dissipation per package based on package heattransfer, not device powerconsumption

- 1.5 W




10. Static characteristics

Table 8: DC electrical characteristicsVDD = 2.4 V to 3.6 V unless otherwise specified.Tamb = −40 °C to +85 °C for industrial, unless otherwise specified.

Symbol Parameter Conditions Min Typ [1] Max Unit

IDD(oper) power supply current, operating 3.6 V; 12 MHz [2] - 9 15 mA

3.6 V; 18 MHz [2] - 11.5 20 mA

IDD(idle) power supply current, Idle mode 3.6 V; 12 MHz [2] - 3.25 5 mA

3.6 V; 18 MHz [2] - 5 7 mA

IDD(PD) power supply current, Power-downmode, voltage comparatorspowered-down

3.6 V [2] - 55 80 µA

IDD(TPD) power supply current, TotalPower-down mode

3.6 V [2] - 1 5 µA

(dVDD/dt)r VDD rise rate - - 2 mV/µs

(dVDD/dt)f VDD fall rate - - 50 mV/µs

VPOR Power-on reset detect voltage - - 0.2 V

VRAM RAM keep-alive voltage 1.5 - - V

Vth(HL) negative-going threshold voltage except SCL, SDA 0.22VDD 0.4VDD - V

VIL LOW-level input voltage SCL, SDA only −0.5 - 0.3VDD V

Vth(LH) positive-going threshold voltage except SCL, SDA - 0.6VDD 0.7VDD V

VIH HIGH-level input voltage SCL, SDA only 0.7VDD - 5.5 V

Vhys hysteresis voltage Port 1 - 0.2VDD - V

VOL LOW-level output voltage; all ports,all modes except Hi-Z[3]

IOL = 20 mA - 0.6 1.0 V

IOL = 3.2 mA - 0.2 0.3 V

VOH HIGH-level output voltage IOH = −20 mA;push-pull mode P0.3to P0.7, P1.4, P1.6,P1.7

0.8VDD - - V

IOH = −3.2 mA;push-pull mode, allother ports

VDD − 0.7 VDD − 0.4 - V

IOH = −20 µA;quasi-bidirectionalmode, all ports

VDD − 0.3 VDD − 0.2 - V

Cig input/output pin capacitance [4] - - 15 pF

IIL logical 0 input current, all ports VIN = 0.4 V [5] - - −80 µA

ILI input leakage current, all ports VIN = VIL or VIH[6] - - ±10 µA

ITL logical 1-to-0 transition current,all ports

VIN = 2.0 V atVDD = 3.6 V

[7], [8] −30 - −450 µA

RRST internal reset pull-up resistor 10 - 30 kΩ




[1] Typical ratings are not guaranteed. The values listed are at room temperature, 3 V.

[2] The IDD(oper), IDD(idle), and IDD(PD) specifications are measured using an external clock with the following functions disabled: comparators,brownout detect, and Watchdog timer.

[3] See Table 7 “Limiting values[1]” on page 35 for steady state (non-transient) limits on IOL or IOH. If IOL/IOH exceeds the test condition,VOL/VOH may exceed the related specification.

[4] Pin capacitance is characterized but not tested.

[5] Measured with port in quasi-bidirectional mode.

[6] Measured with port in high-impedance mode.

[7] Ports in quasi-bidirectional mode with weak pull-up (applies to all port pins with pull-ups). Does not apply to open-drain pins.

[8] Port pins source a transition current when used in quasi-bidirectional mode and externally driven from ‘1’ to ‘0’. This current is highestwhen VIN is approximately 2 V.

VBO brownout trip voltage withBOV = ‘0’, BOPD = ‘1’

2.4 V < VDD < 3.6 V 2.40 - 2.70 V

VREF bandgap reference voltage 1.11 1.23 1.34 V

TC(VREF) bandgap temperature coefficient - 10 20 ppm/°C

Table 8: DC electrical characteristics …continuedVDD = 2.4 V to 3.6 V unless otherwise specified.Tamb = −40 °C to +85 °C for industrial, unless otherwise specified.

Symbol Parameter Conditions Min Typ [1] Max Unit




11. Dynamic characteristics

[1] Parameters are valid over operating temperature range unless otherwise specified. Parts are tested to 2 MHz, but are guaranteed tooperate down to 0 Hz.

Table 9: AC characteristicsVDD = 2.4 V to 3.6 V unless otherwise specified.Tamb = −40 °C to +85 °C for industrial, unless otherwise specified.[1]

Symbol Parameter Conditions Variable clock fosc = 12 MHz Unit

Min Max Min Max

fRCOSC internal RC oscillator frequency(nominal f = 7.3728 MHz)

trimmed to ±1%at Tamb = 25 °C

7.189 7.557 7.189 7.557 MHz

fWDOSC internal Watchdog oscillatorfrequency (nominal f = 400 kHz)

320 520 320 520 kHz

fosc oscillator frequency 0 12 - - MHz

tCLCL clock cycle see Figure 13 83 - - - ns

fCLKP CLKLP active frequency 0 8 - - MHz

Glitch filter

glitch rejection, P1.5/RST pin - 50 - 50 ns

signal acceptance, P1.5/RST pin 125 - 125 - ns

glitch rejection, any pin exceptP1.5/RST

- 15 - 15 ns

signal acceptance, any pin exceptP1.5/RST

50 - 50 - ns

External clock

tCHCX HIGH time see Figure 13 33 tCLCL − tCLCX 33 - ns

tCLCX LOW time see Figure 13 33 tCLCL − tCHCX 33 - ns

tCLCH rise time see Figure 13 - 8 - 8 ns

tCHCL fall time see Figure 13 - 8 - 8 ns

Shift register (UART mode 0)

tXLXL serial port clock cycle time 16 tCLCL - 1333 - ns

tQVXH output data set-up to clock risingedge

13 tCLCL - 1083 - ns

tXHQX output data hold after clock risingedge

- tCLCL + 20 - 103 ns

tXHDX input data hold after clock rising edge - 0 - 0 ns

tDVXH input data valid to clock rising edge 150 - 150 - ns




[1] Parameters are valid over operating temperature range unless otherwise specified. Parts are tested to 2 MHz, but are guaranteed tooperate down to 0 Hz.

[2] When using an oscillator frequency above 12 MHz, the reset input function of P1.5 must be enabled. An external circuit is required tohold the device in reset at power-up until VDD has reached its specified level. When system power is removed VDD will fall below theminimum specified operating voltage. When using an oscillator frequency above 12 MHz, in some applications, an external brownoutdetect circuit may be required to hold the device in reset when VDD falls below the minimum specified operating voltage.

Table 10: AC characteristicsVDD = 3.0 V to 3.6 V unless otherwise specified.Tamb = −40 °C to +85 °C for industrial, unless otherwise specified.[1]

Symbol Parameter Conditions Variable clock fosc = 18 MHz Unit

Min Max Min Max

fRCOSC internal RC oscillator frequency(nominal f = 7.3728 MHz)

trimmed to ±1%at Tamb = 25 °C

7.189 7.557 7.189 7.557 MHz

fWDOSC internal Watchdog oscillatorfrequency (nominal f = 400 kHz)

320 520 320 520 kHz

fosc oscillator frequency [2] 0 18 - - MHz

tCLCL clock cycle see Figure 13 55 - - - ns

fCLKP CLKLP active frequency 0 8 - - MHz

Glitch filter

glitch rejection, P1.5/RST pin - 50 - 50 ns

signal acceptance, P1.5/RST pin 125 - 125 - ns

glitch rejection, any pin exceptP1.5/RST

- 15 - 15 ns

signal acceptance, any pin exceptP1.5/RST

50 - 50 - ns

External clock

tCHCX HIGH time see Figure 13 22 tCLCL − tCLCX 22 - ns

tCLCX LOW time see Figure 13 22 tCLCL − tCHCX 22 - ns

tCLCH rise time see Figure 13 - 5 - 5 ns

tCHCL fall time see Figure 13 - 5 - 5 ns

Shift register (UART mode 0)

tXLXL serial port clock cycle time 16 tCLCL - 888 - ns

tQVXH output data set-up to clock risingedge

13 tCLCL - 722 - ns

tXHQX output data hold after clock risingedge

- tCLCL + 20 - 75 ns

tXHDX input data hold after clock rising edge - 0 - 0 ns

tDVXH input data valid to clock rising edge 150 - 150 - ns




Fig 12. Shift register mode timing.

0 1 2 3 4 5 6 7

Valid Valid Valid Valid Valid Valid Valid Valid

tXLXL

002aaa425

Set TI

Set RI

tXHQXtQVXH

tXHDV

tXHDX

Clock

Output Data

Write to SBUF

Input Data

Clear RI

Fig 13. External clock timing.

tCHCL tCLCX

tCHCX

tC

tCLCH

002aaa416

0.2 VDD + 0.9

0.2 VDD - 0.1 V

VDD - 0.5 V

0.45 V

Table 11: AC characteristics, ISP entry modeVDD = 2.4 V to 3.6 V, unless otherwise specified.Tamb = −40 °C to +85 °C for industrial, unless otherwise specified.

Symbol Parameter Conditions Min Typ Max Unit

tVR RST delay from VDD active 50 - - µs

tRH RST HIGH time 1 - 32 µs

tRL RST LOW time 1 - - µs

Fig 14. ISP entry waveform.

002aaa426

VDD

RST

tRL

tVR tRH




12. Comparator electrical characteristics

[1] This parameter is characterized, but not tested in production.

Table 12: Comparator electrical characteristicsVDD = 2.4 V to 3.6 V, unless otherwise specified.Tamb = −40 °C to +85 °C for industrial, unless otherwise specified.

Symbol Parameter Conditions Min Typ Max Unit

VIO offset voltage comparator inputs - - ±20 mV

VCR common mode range comparator inputs 0 - VDD − 0.3 V

CMRR common mode rejection ratio [1] - - −50 dB

response time - 250 500 ns

comparator enable to output valid - - 10 µs

IIL input leakage current, comparator 0 < VIN < VDD - - ±10 µA




13. Package outline

Fig 15. TSSOP20 (SOT360-1).

UNIT A1 A2 A3 bp c D (1) E (2) (1)e HE L L p Q Zywv θ

REFERENCESOUTLINEVERSION

EUROPEANPROJECTION ISSUE DATE

IEC JEDEC JEITA

mm 0.150.05

0.950.80

0.300.19

0.20.1

6.66.4

4.54.3

0.656.66.2

0.40.3

0.50.2

80

o

o0.13 0.10.21

DIMENSIONS (mm are the original dimensions)

Notes

1. Plastic or metal protrusions of 0.15 mm maximum per side are not included.

2. Plastic interlead protrusions of 0.25 mm maximum per side are not included.

0.750.50

SOT360-1 MO-15399-12-2703-02-19

w Mbp

D

Z

e

0.25

1 10

20 11

pin 1 index

θ

AA1

A2

Lp

Q

detail X

L

(A )3

HE

E

c

v M A

XA

y

0 2.5 5 mm

scale

TSSOP20: plastic thin shrink small outline package; 20 leads; body width 4.4 mm SOT360-1

Amax.

1.1




Fig 16. DIP20 (SOT146-1).

UNIT Amax.

1 2 b1 c D E e MHL

REFERENCESOUTLINEVERSION

EUROPEANPROJECTION ISSUE DATE

IEC JEDEC JEITA

mm

inches

DIMENSIONS (inch dimensions are derived from the original mm dimensions)

SOT146-199-12-2703-02-13

A min.

A max. b Z

max.wMEe1

1.731.30

0.530.38

0.360.23

26.9226.54

6.406.22

3.603.05

0.2542.54 7.628.257.80

10.0 8.3

24.2 0.51 3.2

0.0680.051

0.0210.015

0.0140.009

1.0601.045

0.250.24

0.140.12

0.010.1 0.30.320.31

0.390.33

0.0780.17 0.02 0.13

SC-603MS-001

MH

c

(e )1

ME

A

L

seat

ing

plan

e

A1

w Mb1

e

D

A2

Z

20

1

11

10

b

E

pin 1 index

0 5 10 mm

scale

Note

1. Plastic or metal protrusions of 0.25 mm (0.01 inch) maximum per side are not included.

(1)(1) (1)

DIP20: plastic dual in-line package; 20 leads (300 mil) SOT146-1




14. Revision history

Table 13: Revision history

Rev Date CPCN Description

08 20041215 - Product data (9397 750 14469)

Modification:

• Added 18 MHz information.

07 20041203 - Product data (9397 750 14251)

06 20031121 - Product data (9397 750 12285); ECN 853-2403 01-A14557 of 18 November 2003

05 20031007 - Product data (9397 750 12121); ECN 853-2403 30391 of 30 September 2003

04 20030909 - Product data (9397 750 11945); ECN 853-2403 30305 of 5 September 2003

03 20030811 - Preliminary data (9397 750 11786)

02 20030522 - Objective data (9397 750 11532)

01 20030505 - Preliminary data (9397 750 11387)




15. Data sheet status

[1] Please consult the most recently issued data sheet before initiating or completing a design.

[2] The product status of the device(s) described in this data sheet may have changed since this data sheet was published. The latest information is available on the Internet atURL http://www.semiconductors.philips.com.

[3] For data sheets describing multiple type numbers, the highest-level product status determines the data sheet status.

16. Definitions

Short-form specification — The data in a short-form specification isextracted from a full data sheet with the same type number and title. Fordetailed information see the relevant data sheet or data handbook.

Limiting values definition — Limiting values given are in accordance withthe Absolute Maximum Rating System (IEC 60134). Stress above one ormore of the limiting values may cause permanent damage to the device.These are stress ratings only and operation of the device at these or at anyother conditions above those given in the Characteristics sections of thespecification is not implied. Exposure to limiting values for extended periodsmay affect device reliability.

Application information — Applications that are described herein for anyof these products are for illustrative purposes only. Philips Semiconductorsmake no representation or warranty that such applications will be suitable forthe specified use without further testing or modification.

17. Disclaimers

Life support — These products are not designed for use in life supportappliances, devices, or systems where malfunction of these products canreasonably be expected to result in personal injury. Philips Semiconductors

customers using or selling these products for use in such applications do soat their own risk and agree to fully indemnify Philips Semiconductors for anydamages resulting from such application.

Right to make changes — Philips Semiconductors reserves the right tomake changes in the products - including circuits, standard cells, and/orsoftware - described or contained herein in order to improve design and/orperformance. When the product is in full production (status ‘Production’),relevant changes will be communicated via a Customer Product/ProcessChange Notification (CPCN). Philips Semiconductors assumes noresponsibility or liability for the use of any of these products, conveys nolicence or title under any patent, copyright, or mask work right to theseproducts, and makes no representations or warranties that these products arefree from patent, copyright, or mask work right infringement, unless otherwisespecified.

18. Licenses

Level Data sheet status [1] Product status [2][3] Definition

I Objective data Development This data sheet contains data from the objective specification for product development. PhilipsSemiconductors reserves the right to change the specification in any manner without notice.

II Preliminary data Qualification This data sheet contains data from the preliminary specification. Supplementary data will be publishedat a later date. Philips Semiconductors reserves the right to change the specification without notice, inorder to improve the design and supply the best possible product.

III Product data Production This data sheet contains data from the product specification. Philips Semiconductors reserves theright to make changes at any time in order to improve the design, manufacturing and supply. Relevantchanges will be communicated via a Customer Product/Process Change Notification (CPCN).

Purchase of Philips I 2C components

Purchase of Philips I2C components conveys a licenseunder the Philips’ I2C patent to use the components in theI2C system provided the system conforms to the I2Cspecification defined by Philips. This specification can beordered using the code 9398 393 40011.



Contact informationFor additional information, please visit http://www.semiconductors.philips.com .For sales office addresses, send e-mail to: [email protected] . Fax: +31 40 27 24825

© Koninklijke Philips Electronics N.V. 2004.Printed in the U.S.A.

All rights are reserved. Reproduction in whole or in part is prohibited without the priorwritten consent of the copyright owner.

The information presented in this document does not form part of any quotation orcontract, is believed to be accurate and reliable and may be changed without notice. Noliability will be accepted by the publisher for any consequence of its use. Publicationthereof does not convey nor imply any license under patent- or other industrial orintellectual property rights.

Date of release: 15 December 2004 Document order number: 9397 750 14469

Contents


1 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1 Principal features . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.2 Additional features . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

3 Ordering information. . . . . . . . . . . . . . . . . . . . . . . . . . 33.1 Ordering options . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

4 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

5 Pinning information. . . . . . . . . . . . . . . . . . . . . . . . . . . 55.1 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55.2 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

6 Logic symbol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

7 Special function registers. . . . . . . . . . . . . . . . . . . . . . 9

8 Functional description . . . . . . . . . . . . . . . . . . . . . . . 148.1 Enhanced CPU . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148.2 Clocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148.2.1 Clock definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148.2.2 CPU clock (OSCCLK) . . . . . . . . . . . . . . . . . . . . . . . 148.2.3 Low speed oscillator option . . . . . . . . . . . . . . . . . . . 148.2.4 Medium speed oscillator option . . . . . . . . . . . . . . . . 148.2.5 High speed oscillator option . . . . . . . . . . . . . . . . . . . 148.2.6 Clock output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158.3 On-chip RC oscillator option . . . . . . . . . . . . . . . . . . 158.4 Watchdog oscillator option . . . . . . . . . . . . . . . . . . . . 158.5 External clock input option . . . . . . . . . . . . . . . . . . . . 158.6 CPU Clock (CCLK) wake-up delay. . . . . . . . . . . . . . 178.7 CPU Clock (CCLK) modification: DIVM register . . . 178.8 Low power select . . . . . . . . . . . . . . . . . . . . . . . . . . . 178.9 Memory organization . . . . . . . . . . . . . . . . . . . . . . . . 178.10 Data RAM arrangement . . . . . . . . . . . . . . . . . . . . . . 188.11 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188.11.1 External interrupt inputs . . . . . . . . . . . . . . . . . . . . . . 188.12 I/O ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198.12.1 Port configurations . . . . . . . . . . . . . . . . . . . . . . . . . . 198.12.2 Quasi-bidirectional output configuration. . . . . . . . . . 208.12.3 Open-drain output configuration. . . . . . . . . . . . . . . . 208.12.4 Input-only configuration . . . . . . . . . . . . . . . . . . . . . . 208.12.5 Push-pull output configuration . . . . . . . . . . . . . . . . . 208.12.6 Port 0 analog functions . . . . . . . . . . . . . . . . . . . . . . 208.12.7 Additional port features . . . . . . . . . . . . . . . . . . . . . . 218.13 Power monitoring functions . . . . . . . . . . . . . . . . . . . 218.13.1 Brownout detection . . . . . . . . . . . . . . . . . . . . . . . . . 218.13.2 Power-on detection . . . . . . . . . . . . . . . . . . . . . . . . . 218.14 Power reduction modes . . . . . . . . . . . . . . . . . . . . . . 218.14.1 Idle mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228.14.2 Power-down mode . . . . . . . . . . . . . . . . . . . . . . . . . . 228.14.3 Total Power-down mode. . . . . . . . . . . . . . . . . . . . . . 228.15 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228.15.1 Reset vector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238.16 Timers/counters 0 and 1 . . . . . . . . . . . . . . . . . . . . . 238.16.1 Mode 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238.16.2 Mode 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238.16.3 Mode 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248.16.4 Mode 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

8.16.5 Mode 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248.16.6 Timer overflow toggle output. . . . . . . . . . . . . . . . . . . 248.17 Real-Time clock/system timer. . . . . . . . . . . . . . . . . . 248.18 UART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248.18.1 Mode 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248.18.2 Mode 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258.18.3 Mode 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258.18.4 Mode 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258.18.5 Baud rate generator and selection . . . . . . . . . . . . . . 258.18.6 Framing error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258.18.7 Break detect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268.18.8 Double buffering . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268.18.9 Transmit interrupts with double buffering

enabled (Modes 1, 2 and 3) . . . . . . . . . . . . . . . . . . . 268.18.10 The 9th bit (bit 8) in double buffering (Modes 1, 2 and

3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268.19 I2C-bus serial interface . . . . . . . . . . . . . . . . . . . . . . . 278.20 Analog comparators . . . . . . . . . . . . . . . . . . . . . . . . . 298.20.1 Internal reference voltage . . . . . . . . . . . . . . . . . . . . . 298.20.2 Comparator interrupt. . . . . . . . . . . . . . . . . . . . . . . . . 308.20.3 Comparators and power reduction modes . . . . . . . . 308.21 Keypad interrupt (KBI) . . . . . . . . . . . . . . . . . . . . . . . 308.22 Watchdog timer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318.23 Additional features . . . . . . . . . . . . . . . . . . . . . . . . . . 318.23.1 Software reset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318.23.2 Dual data pointers. . . . . . . . . . . . . . . . . . . . . . . . . . . 318.24 Flash program memory. . . . . . . . . . . . . . . . . . . . . . . 328.24.1 General description. . . . . . . . . . . . . . . . . . . . . . . . . . 328.24.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328.24.3 ISP and IAP capabilities of

the P89LPC920/921/922/9221 . . . . . . . . . . . . . . . . 328.25 User configuration bytes . . . . . . . . . . . . . . . . . . . . . . 348.26 User sector security bytes . . . . . . . . . . . . . . . . . . . . 34

9 Limiting values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

10 Static characteristics . . . . . . . . . . . . . . . . . . . . . . . . . 36

11 Dynamic characteristics . . . . . . . . . . . . . . . . . . . . . . 38

12 Comparator electrical characteristics . . . . . . . . . . . 41

13 Package outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

14 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

15 Data sheet status . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

16 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

17 Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

18 Licenses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

P89LPC920/921/922/9221 8-bit microcontrollers with two ... · PDF filePhilips Semiconductors...

Documents

Transcript of P89LPC920/921/922/9221 8-bit microcontrollers with two ... · PDF filePhilips Semiconductors...