Skovbrynet / Mbed 2 deprecated I2C_Debug_LCD

I2C

Dependencies:   TextLCD mbed

Fork of I2C_Debug_for_RealTerm by jim hamblen

main.cpp@3:8e2db72d0d7d, 2016-02-29 (annotated)

Committer:
Tuxitheone
Date:
Mon Feb 29 18:57:56 2016 +0000
Revision:
3:8e2db72d0d7d
Parent:
2:fa8c916b42a9 
I2C

Who changed what in which revision?

UserRevisionLine numberNew contents of line
4180_1 0:0c54b73b002c 1 #include "mbed.h"
Tuxitheone 3:8e2db72d0d7d 2 #include "TextLCD.h"
Tuxitheone 3:8e2db72d0d7d 3
4180_1 0:0c54b73b002c 4 DigitalOut myled(LED1);
4180_1 0:0c54b73b002c 5 Serial pc(USBTX, USBRX);
4180_1 0:0c54b73b002c 6 I2C i2c(p9,p10);
Tuxitheone 3:8e2db72d0d7d 7 TextLCD lcd(p15, p16, p17, p18, p19, p20, TextLCD::LCD20x2); // 4bit bus: rs, e, d4-d7
4180_1 0:0c54b73b002c 8
4180_1 0:0c54b73b002c 9 int main() {
4180_1 1:be1498ba7fb4 10 char last_command=0;
4180_1 2:fa8c916b42a9 11 char previous_command=0;
4180_1 1:be1498ba7fb4 12 char current_char=0;
4180_1 1:be1498ba7fb4 13 char address=0;
4180_1 1:be1498ba7fb4 14 char data [255];
4180_1 1:be1498ba7fb4 15 char current_byte=0;
4180_1 0:0c54b73b002c 16 char cmd[255];
4180_1 0:0c54b73b002c 17 int cmd_count=0;
4180_1 1:be1498ba7fb4 18 int data_count=0;
4180_1 1:be1498ba7fb4 19 int read=0;
4180_1 1:be1498ba7fb4 20 int write=0;
4180_1 1:be1498ba7fb4 21 int first_data_byte=0;
4180_1 0:0c54b73b002c 22 int i=0;
4180_1 1:be1498ba7fb4 23
4180_1 0:0c54b73b002c 24 myled=1;
4180_1 0:0c54b73b002c 25 i2c.frequency(75000);
4180_1 0:0c54b73b002c 26 i2c.start();
4180_1 1:be1498ba7fb4 27 i2c.stop();
4180_1 2:fa8c916b42a9 28 // Send a start message to RealTerm
Tuxitheone 3:8e2db72d0d7d 29 lcd.printf("\fmbed I2C debug tool ready\n\r");
4180_1 2:fa8c916b42a9 30 // Scan for I2C devices that reply with ack
4180_1 2:fa8c916b42a9 31 for (i=0; i<=254; i=i+2) {
4180_1 2:fa8c916b42a9 32 if (i2c.read(i, &data[0], 1) ==0) printf("I2C device detected at address=%2.2X\n\r", i);
4180_1 2:fa8c916b42a9 33 }
4180_1 2:fa8c916b42a9 34 data[0]=0;
4180_1 0:0c54b73b002c 35 i2c.start();
4180_1 1:be1498ba7fb4 36 i2c.stop();
4180_1 1:be1498ba7fb4 37 // Loop processing command strings from RealTerm
4180_1 0:0c54b73b002c 38 while (1) {
4180_1 1:be1498ba7fb4 39 current_char = pc.getc();
4180_1 1:be1498ba7fb4 40 // Is it a two character ASCII string data byte value
4180_1 2:fa8c916b42a9 41 if ((current_char <='F') && (current_char !='?')) {
4180_1 1:be1498ba7fb4 42 // convert to a binary byte
4180_1 1:be1498ba7fb4 43 if (current_char <='9') current_byte = current_char - '0';
4180_1 1:be1498ba7fb4 44 else current_byte =current_char +10 -'A';
4180_1 1:be1498ba7fb4 45 current_char = pc.getc();
Tuxitheone 3:8e2db72d0d7d 46 if (current_char >'F') lcd.printf("error|\n\r");
4180_1 1:be1498ba7fb4 47 if (current_char <='9') current_byte = (current_byte <<4) | (current_char - '0');
4180_1 1:be1498ba7fb4 48 else current_byte = (current_byte <<4)|(current_char +10 -'A');
4180_1 1:be1498ba7fb4 49 // first byte after S command is the I2C address
4180_1 1:be1498ba7fb4 50 if (first_data_byte==1) {
4180_1 1:be1498ba7fb4 51 first_data_byte=0;
4180_1 1:be1498ba7fb4 52 address=current_byte;
Tuxitheone 3:8e2db72d0d7d 53 lcd.printf(" -I2C address=%2.2X ", address);
4180_1 1:be1498ba7fb4 54 //Odd I2C address is a read and even is a write
4180_1 1:be1498ba7fb4 55 if ((address & 0x01) == 0) write=1;
4180_1 1:be1498ba7fb4 56 else read=1;
4180_1 1:be1498ba7fb4 57 } else
4180_1 1:be1498ba7fb4 58 // Read in cmd bytes for write
4180_1 1:be1498ba7fb4 59 if ((last_command == 'S')&&(read==0)) {
4180_1 1:be1498ba7fb4 60 cmd[cmd_count]=current_byte;
4180_1 1:be1498ba7fb4 61 cmd_count++;
4180_1 0:0c54b73b002c 62 }
4180_1 1:be1498ba7fb4 63 // number of bytes for a read
4180_1 1:be1498ba7fb4 64 if ((last_command =='R')||(read==1)) data_count=current_byte;
4180_1 1:be1498ba7fb4 65 } else {
4180_1 1:be1498ba7fb4 66 // Not a number - it is a command character
4180_1 1:be1498ba7fb4 67 last_command = current_char;
4180_1 1:be1498ba7fb4 68 switch (last_command) {
4180_1 1:be1498ba7fb4 69 // Start
4180_1 1:be1498ba7fb4 70 case 'S':
4180_1 2:fa8c916b42a9 71 if (previous_command == 'S') i2c.start();
4180_1 1:be1498ba7fb4 72 first_data_byte=1;
4180_1 1:be1498ba7fb4 73 break;
4180_1 1:be1498ba7fb4 74 // Stop
4180_1 1:be1498ba7fb4 75 case 'P':
4180_1 1:be1498ba7fb4 76 // Do the I2C write
4180_1 1:be1498ba7fb4 77 if (write==1) {
Tuxitheone 3:8e2db72d0d7d 78 lcd.printf(" write ");
Tuxitheone 3:8e2db72d0d7d 79 if (i2c.write(address,cmd,cmd_count)!=0) lcd.printf(" No Ack! ");
4180_1 1:be1498ba7fb4 80 for (i=0; i<cmd_count; i++)
Tuxitheone 3:8e2db72d0d7d 81 lcd.printf(" cmd=%2.2X ", cmd[i]);
4180_1 0:0c54b73b002c 82 }
4180_1 1:be1498ba7fb4 83 // Do the I2C read
4180_1 1:be1498ba7fb4 84 if (read==1) {
Tuxitheone 3:8e2db72d0d7d 85 lcd.printf(" read ");
Tuxitheone 3:8e2db72d0d7d 86 if (i2c.read(address, data, data_count) != 0) lcd.printf(" No Ack! ");
4180_1 1:be1498ba7fb4 87 for (i=0; i<data_count; i++)
Tuxitheone 3:8e2db72d0d7d 88 lcd.printf(" data=%2.2X ",data[i]);
4180_1 1:be1498ba7fb4 89 }
4180_1 1:be1498ba7fb4 90 // reset values for next I2C operation
4180_1 1:be1498ba7fb4 91 i2c.stop();
Tuxitheone 3:8e2db72d0d7d 92 lcd.printf("\n\r");
4180_1 1:be1498ba7fb4 93 read=0;
4180_1 1:be1498ba7fb4 94 data_count=0;
4180_1 1:be1498ba7fb4 95 cmd_count=0;
4180_1 1:be1498ba7fb4 96 write=0;
4180_1 1:be1498ba7fb4 97 first_data_byte=0;
4180_1 1:be1498ba7fb4 98 break;
4180_1 1:be1498ba7fb4 99 // Read after write
4180_1 1:be1498ba7fb4 100 case 'R':
4180_1 1:be1498ba7fb4 101 read=1;
4180_1 1:be1498ba7fb4 102 break;
4180_1 1:be1498ba7fb4 103 // Status request
4180_1 1:be1498ba7fb4 104 case '?':
Tuxitheone 3:8e2db72d0d7d 105 lcd.printf(" mbed ready \n\r");
4180_1 1:be1498ba7fb4 106 break;
4180_1 1:be1498ba7fb4 107 // Unknown or unimplemented command
4180_1 1:be1498ba7fb4 108 default:
Tuxitheone 3:8e2db72d0d7d 109 lcd.printf(" unknown command \n\r");
4180_1 1:be1498ba7fb4 110 break;
4180_1 1:be1498ba7fb4 111 }
4180_1 2:fa8c916b42a9 112 previous_command = last_command;
4180_1 0:0c54b73b002c 113 }
4180_1 0:0c54b73b002c 114 }
4180_1 0:0c54b73b002c 115 }