software/main.c

   1 /*
   2 see README.txt for details.
   3
   4 chris <cliechti@gmx.net>
   5 */
   6 #include "hardware.h"
   7 #include <stdlib.h>
   8 #include <stdio.h>
   9 #include "swuart.h"
  10 #include "fll.h"
  11
  12 /**
  13 Delay function.
  14 */
  15 void delay(unsigned int d) {
  16    while(d--) {
  17       nop();
  18       nop();
  19    }
  20 }
  21
  22 /**
  23 Main function with init an an endless loop that is synced with the
  24 interrupts trough the lowpower mode.
  25 */
  26 int main(void) {
  27     int reading = 0;
  28     int pos = 0;
  29     char buf[40];
  30     int led = 0;
  31
  32     WDTCTL = WDTCTL_INIT;               //Init watchdog timer
  33
  34     P1OUT  = P1OUT_INIT;                //Init output data of port1
  35     P1SEL  = P1SEL_INIT;                //Select port or module -function on port1
  36     P1DIR  = P1DIR_INIT;                //Init port direction register of port1
  37     P1IES  = P1IES_INIT;                //init port interrupts
  38     P1IE   = P1IE_INIT;
  39
  40     P2OUT  = P2OUT_INIT;                //Init output data of port2
  41     P2SEL  = P2SEL_INIT;                //Select port or module -function on port2
  42     P2DIR  = P2DIR_INIT;                //Init port direction register of port2
  43     P2IES  = P2IES_INIT;                //init port interrupts
  44     P2IE   = P2IE_INIT;
  45
  46     P3DIR  = 0xff;
  47     P3OUT  = 0xff;                      //light LED during init
  48     delay(65535);                       //Wait for watch crystal startup
  49     delay(65535);
  50 //  fllInit();                          //Init FLL to desired frequency using the 32k768 cystal as reference.
  51     P3OUT  = 0x00;                      //switch off LED
  52
  53     TACTL  = TACTL_AFTER_FLL;           //setup timer (still stopped)
  54     CCTL0  = CCIE|CAP|CM_2|CCIS_1|SCS;  //select P2.2 with UART signal
  55     CCTL1  = 0;                         //
  56     CCTL2  = 0;                         //
  57     TACTL |= MC1;                       //start timer
  58
  59     eint();                             //enable interrupts
  60
  61     printf("\r\n====== openMSP430 in action ======\r\n");   //say hello
  62     printf("\r\nSimple Line Editor Ready\r\n");   //say hello
  63
  64     while (1) {                         //main loop, never ends...
  65         printf("> ");                   //show prompt
  66         reading = 1;
  67         while (reading) {               //loop and read characters
  68             LPM0;                       //sync, wakeup by irq
  69
  70             led++;                      // Some lighting...
  71             if (led==9) {
  72               led = 0;
  73             }
  74             P3OUT = (0x01 << led);
  75
  76             switch (rxdata) {
  77                 //process RETURN key
  78                 case '\r':
  79                 //case '\n':
  80                     printf("\r\n");     //finish line
  81                     buf[pos++] = 0;     //to use printf...
  82                     printf(":%s\r\n", buf);
  83                     reading = 0;        //exit read loop
  84                     pos = 0;            //reset buffer
  85                     break;
  86                 //backspace
  87                 case '\b':
  88                     if (pos > 0) {      //is there a char to delete?
  89                         pos--;          //remove it in buffer
  90                         putchar('\b');  //go back
  91                         putchar(' ');   //erase on screen
  92                         putchar('\b');  //go back
  93                     }
  94                     break;
  95                 //other characters
  96                 default:
  97                     //only store characters if buffer has space
  98                     if (pos < sizeof(buf)) {
  99                         putchar(rxdata);     //echo
 100                         buf[pos++] = rxdata; //store
 101                     }
 102             }
 103         }
 104     }
 105 }
 106