Understanding IsoPod™

What is IsoPod™?• Real Time Controller

– IsoMax™ for Multitasking– DSP Core for speed, 40 MIP’s– Motion Control features: PWM, Quadrature,

Timers, A/D, GPIO, 2 SCI, 1 SPI, etc.

– Networking features: CAN Bus V2.0A/B

• Size: 1.2” x 3.3”• Price: $99 single qty.

IsoPod™ Overview

Hardware

Software

Applications

Connectors

Packages

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IsoPod™ Overview

• Here is a larger view of the graphic.

1. Hardware Feature: LED’s

• Three On Board LED’s– Red– Yellow– Green

2. Hardware Feature: GPIO

• 16 General Purpose Input Output lines– PA0 - 7– PB0 – 7– Programmable edge sensitive inputs

3. Hardware Feature: SCI

• Serial Communication Interface (SCI) full-duplex serial channel– One RS-232

– One RS422/485

– Programmable Baud Rates, • 38,400

• 19,200

• 9600

• 4800

• 1200

4. Hardware Feature: SPI

• Serial Peripheral Interface (SPI)– Full-duplex synchronous operation on four-

wire interface– Master or Slave– Programmable # of bits

5. Hardware Feature: A/D

• 8-ch 12-bit AD– Continuous Conversions

• 1.2us (6 ADC cycles)

– Single ended or differential inputs– ADC can be sync’d with PWM

6. Hardware Feature: PWM

• 12-channel PWM module – 15-bit counter with programmable resolutions

down to 25ns– Twelve independent outputs,– or Six complementary pairs of outputs, or

combinations– 8 Fault Inputs– 6 Current Status inputs

7. Hardware Feature: Timers

• Sixteen Timers (eight may be used in quadrature)– 16-bit timers– Count up/down, Cascadable– Pair for simple quadrature– Pair for step and direction– Programmable as input capture or output compare – Input capture trigger rising edge, falling edge, or any

edge – Output capture action

Set, reset or toggle – External sync input

8. Hardware Feature: Quad.

• Two Quadrature Decoder (uses eight timers)– 32-bit position counter– 16-bit position difference register– 16-bit revolution counter – 40MHz count frequency (up to)– Logic to decoder quadrature signals – Configurable digital filter

for inputs – Watchdog timer

to detect stalled shaft

9. Hardware Feature: CAN

• CAN 2.0 A/B module for networking– Programmable bit rate up to 1Mbit: Multiple boards

can be networked (MSCAN)

– Ideal for harsh or noisy environments, like automotive applications

– CAN is a serial bus system especially suited to interconnect smart devices to build smart systems or sub-systems.Ref:http://www.can-cia.org/can/

10. Hardware Feature: JTAG

• JTAG port for CPU debugging– Examine registers, memory, peripherals– Set breakpoints– Step or trace instructions

11. Hardware Feature: COP

• Watch Dog Timer

• COP module

• Low Voltage Detector for Reset– S80728HN

12. Hardware Feature: PWR

Processor has special operating modes:

• Low Voltage Mode

• Stop Mode

• Wait Mode

13. Hardware Feature: DRV

On Board level translation for

• RS232: MAX3221

• RS422: MAX3483

• CAN: TJA1050 CAN Transceiver

14. Hardware Feature: REG

On Board Voltage Regulation

• LM2937 5V

• LM3940 3.3V

Connector OverviewJ1 Ser., Power, General

Purpose I/OSerial, Power, Ports PA0 – PA7, PB0 – PB7

J2 JTAG connector CPU Port

J3 SPI SCLK, MISO, MOSI, SS, PD0, PD1, PD2, PD3

J4 RS-422/485 Serial Port -RCV, +RCV, -XMT, +XMT

J5 CAN BUS Network Port CANL, CANH

J6 Servo Motor Outputs x 12 PWM, +V, GND

J7 Motor Encoder x 2 Quadrature, Fault0, Fault1, Fault2, IS0, IS1, IS2

J8 A/D Various A/D0 – A/D7, Various

Connector J1Ser., Power, General Purpose I/O+VIN 24 1 SOUT

GND 23 2 SIN

RST’ 22 3 ATN’

+5V 21 4 GND

PA0 20 5 PB0

PA1 19 6 PB1

PA2 18 7 PB2

PA3 17 8 PB3

PA4 16 9 PB4

PA5 15 10 PB5

PA6 14 11 PB6

PA7 13 12 PB7

Connector J2JTAG connector

+3V 1 2 GND

TDI 3 4 GND

TDO 5 6 TMS

TCK 7 8 DE

RESET’ 9 10 TRST

Connector J3SPI

+3V 1 2 GND

PD0 3 4 SCLK

PD1 5 6 MOSI

PD2 7 8 MISO

PD3 9 10 SS’

Connector J4 RS-422/485 Serial Port

N.C. 1 2 N.C.

+RCV 3 4 -RCV

GND 5 6 GND

-XMT 7 8 +XMT

N.C. 9 10 N.C.

Connector J5CAN BUS Network Port

N.C. 1 2 N.C.

CANL 3 4 CANH

N.C. 5 6 GND

N.C. 7 8 N.C.

N.C. 9 10 N.C.

Connector J6 Servo Motor Outputs x 12

Sig. +V GND

PWMB5 1 2 3

PWMB4 4 5 6

PWMB3 7 8 9

PWMB2 10 11 12

PWMB1 13 14 15

PWMB0 1 6 17 18

PWMA5 19 20 21

PWMA4 22 23 24

PWMA3 25 26 27

PWMA2 28 29 30

PWMA1 31 32 33

PWMA0 34 35 36

Connector J7Motor Encoder x 2

+5V 24 1 FAULTA0

GND 23 2 FAULTA1

TA0 PHA0 22 3 FAULTA2

TA1 PHB0 21 4 ISA0

TA2 IND0 20 5 ISA1

TA3 HM0 19 6 ISA2

+5V 18 7 FAULTB0

GND 17 8 FAULTB1

TB0 PHA1 16 9 FAULTB2

TB1 PHB1 15 10 ISB0

TB2 IND1 14 11 ISB1

TB3 HM1 13 12 ISB2

Connector J8A/D Various

ANA0 24 1 +5V

ANA1 23 2 IRQA’

ANA2 22 3 IRQB’

ANA3 21 4 FAULTB3

ANA4 20 5 FAULTA3

ANA5 19 6 PD5

ANA6 18 7 TC0

ANA7 17 8 TC1

VSSA 16 9 CLKO

VREF 15 10 RSTO’

GND 14 11 RD’

V+ 13 12 WR’

IsoPod™ comes with IsoMax™

Other Languages

The IsoPod™ can be programmed in languages other than IsoMax™.

• Metrowerks sells Code Warrior, a professional level C language IDE

• Max-FORTH is available now from NMI.

• Small C is under development

• Assembler is under development

• BASIC is planned for the future

Real Time Programming

A real time program is one that waits.

Any program that does not wait on something is not a real time program.

Any program that waits on something, other than the program itself, is a real time program.

Conventional Language

In an ordinary high level language, such as C, BASIC, FORTH or JAVA, programs are written flowing from top to bottom. Flow charts are the preferred diagramming tools. A program that must wait on something, simply loops in place. Most conventional languages follow the structured procedural programming paradigm. Structured programming enforces this style of waiting.

Program Counter Capture (PCC)

The Program Counter Capture, is when the program branches backwards on itself to wait. In Structured Programming, the Program Counter Capture is used to implicitly hold state (wait) information. This information is better kept elsewhere (explicitly).

Conventional Multitasking

In a conventional language getting several things done at the same time is tricky. Most programmers must use a Real Time Operating System. A Multitasking Operating System adds much overhead and complexity for switching tasks/contexts.

Concept of Isostructure

The word, Isostructure, has two roots: Iso, meaning equal or “on the same level,” and structure, from the current usage in the Computer Science. Isostructure is structure with no backwards branches, and an enhanced way to branch in multiple forward directions (called polyfurcation) similar to a case statement.

Multitasking vs. Isostructure

turn onheater a

room atoo cold?

room atoo hot?

yes

yes

turn offheater a

start

heatera off?

yes

turn on heater

too cold?

too hot?no

no

turn off heater

start

If Program Counter Capture (PCC) Loops can be avoided, compatible thread-like programs can be interwoven.

Isostructure and Flow Charts

A simple structured flow chart can sometimes be replaced by alternatively styled Isostructured flow charts as shown above. Complex flow charts are too difficult. Structured program was intended to end spaghetti code. Non Isostructure can lead to unruly intertwines of if-then statements. A different programming paradigm is needed.

Finite State Machines

A better way to represent a real time program is with a Finite State Machine. IsoMax is a programming language based on Finite State Machine (FSM) concepts applied to software, with a procedural language (derived from Forth) underneath it. The closest description to the FSM construction type in IsoMax™ is a “One-Hot” “Mealy” type of Timer-Augmented Finite State Machines.

New Paradigm

IsoMax™ is a new language. Why learn a new language? Because the old languages cannot do what IsoMax™ can. Old languages are based on, and reinforce, structured programming. IsoMax™ is based on Isostructured programming. No other language has fully interactive, high-level, real time programming.

IsoMax™ has a new programming paradigm, simply not available any where else.

IsoMax™ Language

The breakthrough in IsoMax™ is the language is inherently “multitasking” without the overhead or complexity of a multitasking operating system (no PCC’s allowed). In IsoMax™ anyone can write simple machines and string them together so they work.

IsoMax™ Programming

You can draw state diagrams instead of flow charts, and then translate the diagrams directly into their state machine equivalents. To program in IsoMax™ you use text to create state machines. The state machines machines can then run in the Virtually Parallel Machine Architecture (VPMA).

IsoMax™ Machines

Each machine in the program is like a hardware component in a mechanical solution. When satisfied with its performance, you install the new machine in a chain of machines. The machine becomes a background feature of the IsoPod™ until you remove it. All tasks are handled on the same level within the machine chain, each running like its own separate little machine.

Create the machine

There are five steps to creating a machine in IsoMax™ text:

• Name the machine

• Identify the machine

• Append states to the machine

• Describe transitions between states

• Test and install

Name the machine

The first program line, tells IsoMax™ to add a new virtual machine. (Any group of characters without a space or a backspace or return will do for a name. Use up to 32 characters. Here the syntax is MACHINE followed by the chosen name.)MACHINE <name1> State Flowchart

Identify the machine

Second program line, identify as the machine to append to. The syntax to do this is to say ON-MACHINE and the name of the machine to work on, which looks like this:ON-MACHINE <name1>

State Flowchart

Append states to the machine

States are the fundamental parts of our virtual machine. A state is a place where the computer’s outputs are stable, or static. Said another way, a state is place where the computer waits. Add states to the machine with a name. The syntax is APPEND-STATE followed by another made-up name.

APPEND-STATE <name2>APPEND-STATE <name3>etc.

State Flowchart

States Are Waits

A real time program is one that waits. A state machine has states, which are explicit places where machines wait.

States are static.

States are not where the processor “does” something, they are where the processor “doesn’t” do anything, but wait… except to see if it is time to stop waiting.

Describe transitionsbetween states

State Flowchart

The rule for changing states along with the action to do, if the rule is met, is called a “Transition”. A transition contains: - the name of the “State” the rule applies to.- the rule, which is called the “Condition”; this is the “when to stop waiting”- the action; “the what to do then” - the name of the “State” to go to is “where to wait after that”.

Transition syntaxas normally used

IN-STATE

<name of state>

CONDITION

<procedural Boolean>

CAUSES

<procedural action>

THEN-STATE

<name of next state>

TO-HAPPEN

Transition syntaxwith extra comments

IN-STATE ( the State the rule applies to )

<name of state>

CONDITION ( when to stop waiting )

<procedural Boolean>CAUSES ( what action to do )

<procedural action>THEN-STATE ( where to wait after that )

<name of next state>

TO-HAPPEN ( ends this Transition definition )

Transitions Details

A transition has four components;.

1) which state it starts in2) the condition necessary to leave3) the action to take when the condition becomes true4) the state to go to. ;.

Why are transitions so verbose? The structure makes the transitions easy to read in human language. ;.

The constructs IN-STATE,CONDITION,CAUSES, THEN-STATE, and TO-HAPPEN are like the five brackets around a table of four things.

Test and install

IsoMax™ is interactive. The machine can be defined and tested in the foreground, and once performance is assured, it can be installed in the machine chain to run with all other machines in the background scheduled machine list. To truly understand IsoPod™ requires understanding how interactivity speeds development. Test the code as it runs, where it runs, while it runs, in real time.

Sample Machine:Thermostat

A thermostat makes a convenient example. The machine is named, Thermostat1.

MACHINE Thermostat1

The machine is identified, ON-MACHINE Thermostat1

The states added, APPEND-STATE Wait-on-low-temp

APPEND-STATE Wait-on-high-temp

Sample Transitions:Thermostat

IN-STATE

wait-on-low-temp

CONDITION

too-cold?

CAUSES

heater-on

THEN-STATE

wait-on-high-temp

TO-HAPPEN

IN-STATE

wait-on-high-temp

CONDITION

too-hot?

CAUSES

heater-off

THEN-STATE

wait-on-low-temp

TO-HAPPEN

The State Diagram

State Machine program execution can easily be made to be multitasking.

State diagrams contain more information with less confusion.

State Flowchart

Equivalent State Diagramfor Thermostat

w ait_onlow _tem p

w ait_onhigh_tem p

hearter_on

too_cold?

hearter_off

too_w arm ?

Sample ComparisonElements in all 3 Chart

1. Wait until too cold

2. Action when too cold (heater on)

3. Where to go next

4. Wait until too hot

5. Action when too hot (heater off)

6. Where to go next

7. Condition for leaving (too cold)

8. Condition for leaving (too hot)

Sample Comparison 1 of 3State Machine vs. Flow Chart

w a i t _ o n

l o w _ t e m p

w a i t _ o n

h i g h _ t e m p

h e a r t e r _ o n

t o o _ c o l d ?

h e a r t e r _ o f f

t o o _ w a r m ?

1

2

4

5

3

6

7 8

Sample Comparison 2 of 3 Isostructured Flow Chart

tu rn on

hea te r a

room a

too co ld?

room a

too ho t?

yes

yes

tu rn o ff

hea te r a

s ta rt

hea te r

a o ff?

yes

12

45

3

6

78

Sample Comparison 3 of 3 Structured Flow Chart

turn on heater

too cold?

too hot?no

no

turn off heater

start

1

2

4

5

3

6

7

8

Sample Comparison of ElementsState Machine vs. Flow Chart

turn on heater

too cold?

too hot?no

no

turn off heater

start

1

2

4

5

3

6

7

8

turn onheater a

room atoo cold?

room atoo hot?

yes

yes

turn offheater a

start

heatera off?

yes1 2

4 5

3

6

78

wait_onlow_temp

wait_onhigh_temp

hearter_on

too_cold?

hearter_off

too_warm?

1

2

4

5

3

6

7 8

Typical IsoPod™ Applications

• Real Time control• Embedded DSP• Instrumentation• Process Control• Network Control• SCADA• Motion Control• Robotics!

Typical Mobile Robot 1:Hexapod: 6 legged walker

• Locomotion: 18 RC Servos– 12 Hardware PWM 4 Timer PWM

• Ranging: 2 RC Servos Pan and Tilt– 2 Timer PWM– 1 Timer pulse measurement

• Foot sensors– 6 A/D channels: Pressure

Typical Mobile Robot 2:Roller: RC Servo

• Locomotion: 2 RC Servos– 2 Hardware PWM

• Ranging and Sensing– up to 10 sensors on RC Servos– 13 Timers for pulse measurement– 8 A/D channels

Typical Mobile Robot 3:Roller: DC Servo

• Locomotion: 2 DC Servos– 8 Hardware PWM– 2 Quadrature feedback (4 Timer lines)

• Ranging: up to 4 sensors on RC Servos– 5 Timers for pulse measurement– 8 A/D channels

T.B.D.

Simple connection

Hook up for development and programming.

IsoMax™ Communications

Programming and interaction with Isomax™ software is text based via the serial channel. A simple terminal program on PC makes efficient development system. Text can be hand entered via terminal, copied from a text editor, or downloaded from a file (*.txt). It’s easy!

MaxTerm program available for download, from NewMicros.

Sample of Maxterm Screen

Sample of Words on Maxterm Screen

Sample of Programming on Maxterm Screen

Sample of Maxterm Help Screen

IsoPod™

Board by itself w/IsoMax™ installed.

(without cable or transformer)

• Price $99

Order Page

Quick Kit

Quick Kit provides IsoPod™, custom made serial cable and DC wall transformer with special connector. Price: $114

Order Page

Development Kit

Development Kit provides IsoPod™, Controller interface board with 2.4" x 3.6" breakable prototype area, serial cable and wall transformer

• Price: $149Order Page

END

“One Hot”

• "One Hot" is a description of an optimization of a state machine in hardware that has an output per state. So rather than the state number being a combination of bits, like a counter, which points to a state, there is one unique output per state.

more on web more on web BACK

“One Hot” continued

• IsoMax™’s software equivalent is the state number. IsoMax™ uses precomputed GOTO’s. When the scheduler executes a machine, it doesn't have to test the state number to find which state it is in, but vectors directly to it. It is the only “hot” state.

BACK

“George H. Mealy”

• "Mealy" was a pioneer in state machine descriptions (1955). Usually a machine is described as either “Mealy” or “Moore” machine, depending on how outputs are done. Moore thought the states themselves do the output (more suitable to a hardware implementation). Mealy thought the transitions do the output (more appropriate for software).

BACK

“Mealy” continued 1

For IsoMax™ the Mealy machine design is preferred on principle. If a state is a wait, and static as its name implies, it shouldn't be doing anything active (no outputs). Doing something active (making or changing outputs) should be limited to the transition between states (Mealy, not Moore).

BACK

“Mealy” continued 2

In a Mealy machine, the transitions do the output. So the state number wasn't necessarily the output. Consequently, a Mealy machine can have two states with identical outputs, but a different state number. A Moore machine cannot.more on web

BACK

Timer-Augmented

Rodney Brooks of MIT AI Lab fame prefers Finite State Machines for modeling robot behavior. But he likes to augment the FSM’s with timers. He calls these Timer-Augmented Finite State Machines. Timers in the IsoPod™ and LOOPVAR’s in IsoMax™ can be used to augment the FSM’s in this way.

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