The miniDragon+ Board and CodeWarrior Lecture L2.1.
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The miniDragon+ Board and CodeWarrior Lecture L2.1
Transcript of The miniDragon+ Board and CodeWarrior Lecture L2.1.
The miniDragon+ Boardand CodeWarrior
Lecture L2.1
miniDragon+
Serial cable
Reset button
Power plug
2 pushbutton switches
A/D Pot
Run/Load switch
7-segment display
I/O headers
Table 1.1 Parallel Ports in the MC9SDP256
PortPort Name DDR Name Available
PinsminiDragon
use
Port T PTT DDRT 7:0
Port S PTS DDRS 7:0 SCI(1:0)
Port M PTM DDRM 7:0 LCD
Port P PTP DDRP 7:0
Port H PTH DDRH 7:0 7-Seg Display
Port J PTJ DDRJ 7,6,1,0
Port AD0 PORTAD0 Input only 7:0 Switches, pot
Port AD1 PORTAD1 Input only 7:0
Port A PORTA DDRA 7:0 Keypad
Port B PORTB DDRB 7:0
Port E PORTE DDRE 7:0 Mode, XIRQ
Port K PORTK DDRK 7, 5:0
Port Data Register
7 6 5 4 3 2 1 0
Px7 Px6 Px5 Px4 Px3 Px2 Px1 Px0 PORTx
Port Data Direction Register
7 6 5 4 3 2 1 0
DDx7 DDx6 DDx5 DDx4 DDx3 DDx2 DDx1 DDx0 DDRx
DDx[7:0]: Data Direction for Port x0 – Input
1 – Output
Registers associated with parallel I/O ports
V2R LED
V2R LED
V1 > V2
No current
Currentlight
no light
V1 < V2
Turning on an LED
A 7-segment display contains seven light emitting diodes (LEDs)
a b c d e f g
a b c d e f g
+5V
CommonAnode
CommonCathode
a
b
c
d
e
f
g
The miniDragon+ board has a common-cathode 7-segment display. This means that all the cathodes are tied together and connected to ground. The output pins 6:0 of Port H are connected through a 1 kW current-limiting resistor to each of the anodes, g – a. In the common-cathode case, an output 1 will turn on a segment and an output 0 will turn it off.
g f e d c b aPort H: bit 6 5 4 3 2 1 0
a b c d e f g
a b c d e f g
+5V
CommonAnode
CommonCathode
a
b
c
d
e
f
g
Programming in Cusing CodeWarrior
LBE_DP256 is a stationery project that we have created that contains the file main.asm which includes over 80 assembly language routines to perform many I/O functions for the MC9S12DP256 microcontroller on the miniDragon+ board.
Example 1a is the default main.c program for a LBE_DP256 project.
// Example 1a: Turn on every other segment on 7-seg display#include <hidef.h> /* common defines and macros */#include <mc9s12dp256.h> /* derivative information */#include "main_asm.h" /* interface to the assembly module */#pragma LINK_INFO DERIVATIVE "mc9s12dp256b"void main(void) { PLL_init(); // set system clock frequency to 24 MHz DDRH = 0xff; // Port H is output PTH = 0x55; // switch on every other segment for(;;) {} /* wait forever */}
Example 1a
Lab 1
Go through the CodeWarrior tutorial in Appendix A.
In this tutorial you will compile and run the C programs for Examples 1 – 4.
