main.cpp

00001 /* Test of canonical input processing using MODSERIAL library by Andy Kirkham.
00002  *
00003  * The RX callback feature is used to echo input and perform basic line editing.
00004  * This happens outside of the main routine which is free to do other things.
00005  *
00006  * Backspace removes previous character from buffer and updates terminal.
00007  * Delete flushes the buffer and updates terminal.
00008  * CR or LF causes an "end of line" flag to be set.
00009  * Other characters are put into the buffer and echoed on terminal.
00010  */
00011 
00012 #define DATE "21 Apr 2011"
00013 #define VERSION "1.00"
00014  
00015 #include "mbed.h"
00016 #include "MODSERIAL.h"
00017 
00018 void serial_command_handler(void);
00019 void flashes3(void);
00020 void flashes4(void);
00021 void rxCallback(MODSERIAL_IRQ_INFO *info);
00022 
00023 DigitalOut led1(LED1);
00024 DigitalOut led2(LED2);
00025 DigitalOut led3(LED3);
00026 DigitalOut led4(LED4);
00027 
00028 MODSERIAL pc(USBTX, USBRX);
00029 
00030 bool eol_flag = false;
00031 char buf[100];
00032 
00033 int main() {
00034 
00035     pc.printf("%c[2J", 0x1B);    //VT100 erase screen
00036     pc.printf("%c[H", 0x1B);     //VT100 home
00037     pc.printf("MODSERIAL test program (Version %s, %s)\n", VERSION, DATE);
00038 
00039     //set up serial rx callback
00040     pc.baud(9600);
00041     pc.attach(&rxCallback, MODSERIAL::RxIrq);
00042 
00043     pc.printf("> ");
00044     while(1) {      //main loop
00045         if (eol_flag) {     //service command line
00046             serial_command_handler();
00047             eol_flag = false;
00048         }
00049         //service an "event"
00050         flashes3();
00051         //and service another one
00052         flashes4();
00053     }
00054 }
00055 
00056 // Serial command handler
00057 
00058 void serial_command_handler(void) {
00059     char *cp;
00060     
00061     led2 = 1;       //light LED2 to show command processing
00062     pc.printf("\n");
00063     //read input into buffer (gets() does not seem to be supported!)
00064     cp = buf;
00065     while (pc.readable() ) {
00066         *cp++ = pc.getc();
00067     }
00068     --cp;           //move back to CR or LF
00069     *cp = '\0';     //terminate buffer
00070     //print buffer length and contents in both ASCII and hex
00071     int i = (int) (cp - buf);
00072     pc.printf("cnt = %d, buf = <%s>\n", i, buf);
00073     cp = buf;
00074     while (i--) {
00075         pc.printf("%02x ", (int) *cp++);
00076     }
00077     pc.printf("\n> ");
00078     led2 = 0;
00079 }
00080 
00081 // Dummy event handlers - flash LED3 or LED4 for a few seconds
00082 
00083 void flashes3(void) {
00084     for (int i = 4; i > 0; i--) {
00085         led3 = 1;
00086         wait(0.25);
00087         led3 = 0;
00088         wait(0.25);
00089     }
00090 }
00091 
00092 void flashes4(void) {
00093     for (int i = 3; i > 0; i--) {
00094         led4 = 1;
00095         wait(0.4);
00096         led4 = 0;
00097         wait(0.4);
00098     }
00099 }
00100 
00101 // Rx callback routine
00102 
00103 void rxCallback(MODSERIAL_IRQ_INFO *info) {
00104 
00105     MODSERIAL *pc = info->serial;
00106 
00107     led1 = !led1;   //toggle LED1 to show char received
00108     char c = pc->rxGetLastChar();
00109     if (c == 0x7f) {    //flush input buffer and erase line on terminal
00110         int i = pc->rxBufferGetCount();
00111         pc->rxBufferFlush();
00112         while (i--) {
00113             pc->putc(0x8);
00114             pc->putc(' ');
00115             pc->putc(0x8);
00116         }
00117     }
00118     else if (c == 0x8) { //remove last char from buffer and erase on terminal
00119         //remove the BS and the previous char
00120         info->rxDiscardLastChar();
00121         info->rxDiscardLastChar();
00122         pc->putc(0x8);
00123         pc->putc(' ');
00124         pc->putc(0x8);
00125     }
00126     else if (c == '\n' || c == '\r') { //end of line, signal command available
00127         eol_flag = true;
00128     }
00129     else {   //echo char on terminal
00130         pc->putc(c);
00131     }
00132 }
00133 
00134 // END