software/main.c

   1 /*
   2 see README.txt for details.
   3
   4 original by: chris <cliechti@gmx.net>
   5
   6 modified by: Vladimir Burian <buriavl2@fel.cvut.cz>
   7 */
   8 #include "hardware.h"
   9 #include <stdlib.h>
  10 #include <stdio.h>
  11 #include "swuart.h"
  12 #include "fll.h"
  13
  14 /**
  15 QuadCounter value
  16 */
  17 inline uint32_t qcount() {
  18   uint32_t result = 0;
  19
  20   result |= QCNTL;
  21   result |= ((uint32_t)QCNTH << 16);
  22
  23   return result;
  24 }
  25
  26 /**
  27 Handling of QuadCounter IRQ
  28 */
  29 interrupt(QCNT_VECTOR) qcount_isr() {
  30   printf("[QCount = 0x%08lX]\n", qcount() >> 2);
  31 }
  32
  33
  34 /**
  35 Delay function.
  36 */
  37 void delay(unsigned int d) {
  38    while(d--) {
  39       nop();
  40       nop();
  41    }
  42 }
  43
  44 /**
  45 Main function with init an an endless loop that is synced with the
  46 interrupts trough the lowpower mode.
  47 */
  48 int main(void) {
  49     int reading = 0;
  50     int pos = 0;
  51     char buf[40];
  52     int led = 0;
  53
  54     WDTCTL = WDTCTL_INIT;               //Init watchdog timer
  55
  56     P1OUT  = P1OUT_INIT;                //Init output data of port1
  57     P1SEL  = P1SEL_INIT;                //Select port or module -function on port1
  58     P1DIR  = P1DIR_INIT;                //Init port direction register of port1
  59     P1IES  = P1IES_INIT;                //init port interrupts
  60     P1IE   = P1IE_INIT;
  61
  62     P2OUT  = P2OUT_INIT;                //Init output data of port2
  63     P2SEL  = P2SEL_INIT;                //Select port or module -function on port2
  64     P2DIR  = P2DIR_INIT;                //Init port direction register of port2
  65     P2IES  = P2IES_INIT;                //init port interrupts
  66     P2IE   = P2IE_INIT;
  67
  68     P3DIR  = 0xff;
  69     P3OUT  = 0xff;                      //light LED during init
  70     delay(65535);                       //Wait for watch crystal startup
  71     delay(65535);
  72 //  fllInit();                          //Init FLL to desired frequency using the 32k768 cystal as reference.
  73     P3OUT  = 0x00;                      //switch off LED
  74
  75     TACTL  = TACTL_AFTER_FLL;           //setup timer (still stopped)
  76     CCTL0  = CCIE|CAP|CM_2|CCIS_1|SCS;  //select P2.2 with UART signal
  77     CCTL1  = 0;                         //
  78     CCTL2  = 0;                         //
  79     TACTL |= MC1;                       //start timer
  80
  81     eint();                             //enable interrupts
  82
  83     printf("\r\n====== openMSP430 in action ======\r\n");   //say hello
  84     printf("\r\nSimple Line Editor Ready\r\n");   //say hello
  85
  86     printf("\n[QCount = 0x%08lX]\n", qcount());
  87
  88     while (1) {                         //main loop, never ends...
  89         printf("> ");                   //show prompt
  90         reading = 1;
  91         while (reading) {               //loop and read characters
  92             LPM0;                       //sync, wakeup by irq
  93
  94             led++;                      // Some lighting...
  95             if (led==9) {
  96               led = 0;
  97             }
  98             P3OUT = (0x01 << led);
  99
 100             switch (rxdata) {
 101                 //process RETURN key
 102                 case '\r':
 103                 //case '\n':
 104                     printf("\r\n");     //finish line
 105                     buf[pos++] = 0;     //to use printf...
 106                     printf(":%s\r\n", buf);
 107                     reading = 0;        //exit read loop
 108                     pos = 0;            //reset buffer
 109                     break;
 110                 //backspace
 111                 case '\b':
 112                     if (pos > 0) {      //is there a char to delete?
 113                         pos--;          //remove it in buffer
 114                         putchar('\b');  //go back
 115                         putchar(' ');   //erase on screen
 116                         putchar('\b');  //go back
 117                     }
 118                     break;
 119                 //other characters
 120                 default:
 121                     //only store characters if buffer has space
 122                     if (pos < sizeof(buf)) {
 123                         putchar(rxdata);     //echo
 124                         buf[pos++] = rxdata; //store
 125                     }
 126             }
 127         }
 128     }
 129 }
 130