#include #include #include #include #include "usart.h" #define BUFSIZE 16 #define CR 0x0D #define BS 0x08 #define EXLITE RB0 // Fluorometer excitation light #define EXLITEBIT TRISB0 #define ON 1 #define OFF 0 #define TRUE 1 #define FALSE 0 void init_timers(void); void measure(unsigned char); void timeset(void); void interrupt isr(void); /* Control program for the Sedimentation Event Sensor Fluorometer * * Revision history * * v 1.2.1 19Aug11 Added error checking to getch() * * v 1.2.0 16Aug11 Fixed bug in timer1 counting routine, * added dark measurement command * v 1.1.0 6Jun11 Changed PIC from 16F876A to 16F628, * changed excitation light bit from RC3 to RB0 * v 1.0.0 3Apr11 Initial release */ __CONFIG(FOSC_HS & WDTE_OFF & PWRTE_OFF & LVP_OFF & CPD_OFF); volatile unsigned char done; // measurement done flag volatile unsigned int msCounter; // number of elapsed millisecs volatile unsigned int integTime; // number of millisecs to integrate volatile unsigned int chlaCount; // count from chlorophyll A PMT volatile unsigned int phycoCount; // count from phycoerythrin PMT void main(void){ char cmdbuf[BUFSIZE]; unsigned char i, c; di(); // disable all interrupts init_timers(); // set up all three timers init_comms(); // set up the USART - settings defined in usart.h EXLITEBIT = 0; // set up exitation light bit as output EXLITE = OFF; // turn light off ei(); // enable all interrupts integTime = 1000; // integrate for 1 sec printf("\r\nSES Fluorometer v1.2.1\r\n"); while(1) { // main loop printf("\r\n> "); // print prompt i = 0; do { c = getch(); if(c == BS) { if(i > 0) { i--; putch(c); putch(' '); putch(c); } // end if } else { cmdbuf[i++] = c; putch(c); } // end if } while(c != CR && i < BUFSIZE); // until CR or buffer full cmdbuf[i-1] = NULL; // get rid of CR // parse command if(!cmdbuf[0]); // empty command, do nothing else if(!strcmp(cmdbuf, "measure")) measure(TRUE); else if(!strcmp(cmdbuf, "dark")) measure(FALSE); else if(!strcmp(cmdbuf, "timeset")) timeset(); else if(!strcmp(cmdbuf, "lighton")) { EXLITE = ON; printf("\r\nlight is ON"); } // end else if else if(!strcmp(cmdbuf, "lightoff")) { EXLITE = OFF; printf("\r\nlight is OFF"); } // end else if else if(!strcmp(cmdbuf, "help") || !strcmp(cmdbuf, "?")) { printf("\r\nValid commands are:\r\n"); printf("measure\t\ttake a measurement\r\n"); printf("dark\t\tmeasure dark count\r\n"); printf("timeset\t\tset integration time\r\n"); printf("lighton\t\tturn light on\r\n"); printf("lightoff\tturn light off\r\n"); printf("help or ?\tprint command list"); } // end if else printf("\r\nInvalid command!"); } // end while } // end main void init_timers(void) { // Timer0 initialization. Timer0 accumulates the phycoerythrin count. // Note: commands that are commented out aren't necessary as they are the // default condition of the registers // T0CS = 1; // clock source is pin RA4 TRISA4 = 1; // make RA4 an input T0SE = 0; // increment on rising edge // TMR0IE = 0; // don't enable interrupt yet // Timer1 initialization. Timer1 accumulates the chlorophyll A count. // TMR1ON = 0; // disable timer for now TMR1CS = 1; // clock source is external pin RB6 TRISB6 = 1; // make RB6 an input nT1SYNC = 1; // don't synchronize clock input // T1OSCEN = 0; // turn off oscillator // T1CONbits..T1CKPS = 0b00; // prescalar divides by 1 TMR1IE = 0; // don't enable interrupt yet // Timer2 initialization. Timer2 times the integration interval. T2CONbits.T2CKPS = 0b01; // prescaler divides 1 us clock by 4 // T2CONbits.TOUTPS = 0b0000; // postscaler divides by 1 PR2 = 249; // reset every 250 x 4 us = 1 ms TMR2ON = 1; // turn on timer2 TMR2IE = 0; // don't enable interrupt yet PEIE = 1; // enable peripheral interrupts } // end init_timers() void measure(unsigned char light) { printf("\r\ntaking measurement..."); done = FALSE; // measurement in progress phycoCount = 0; // clear counters chlaCount = 0; msCounter = 0; // turn light on here if(light) { EXLITE = ON; // turn light on if not dark measurement } // end if TMR2 = 0; // clear timer2 count TMR2IF = 0; // clear timer2 event flag TMR2IE = 1; // enable timer2 interrupt TMR0 = 0; // clear timer0 count, it's already counting TMR0IF = 0; // clear timer0 event flag TMR0IE = 1; // enable timer0 interrupt TMR1 = 0; // clear timer1 count TMR1ON = 1; // start timer1 counting TMR1IE = 1; // enable timer1 interrupt while(!done) { // wait until measurement done // the interrupt service routine will turn off the light } // end while printf("\r\n%u %u %u", integTime, chlaCount, phycoCount); } // end measure() void timeset(void) { unsigned int input; char inbuf[10]; printf("\r\nEnter integration time in milliseconds (1 - 10000): "); gets(inbuf); input = atoi(inbuf); if(input > 0 && input <= 10000) { integTime = input; printf("\r\nIntegration time set to %d ms", integTime); } else { printf("\r\nInvalid time!"); } // end if } // end timeset() void interrupt isr(void){ // Timer2 code if((TMR2IE)&&(TMR2IF)) { // another ms has passed if(msCounter++ >= integTime) { TMR1ON = 0; // stop timer1 count if(TMR0IE) { // if not overflow phycoCount += TMR0; // capture the timer0 count while still counting } // end if if(TMR1IE) { // if not overflow chlaCount = TMR1; // capture the timer1 count } // end if // turn light off here EXLITE = OFF; // turn light off TMR2IE = 0; // disable all timer interrupts TMR0IE = 0; TMR1IE = 0; done = TRUE; // notify that measurement is done } // end if TMR2IF = 0; // clear event flag } /* end if */ // Timer0 code if((TMR0IE)&&(TMR0IF)) { // timer0 has rolled over phycoCount += 256; // add to phyco count if(phycoCount >> 8 == 0) { // if accumulator overflow phycoCount = 65535; // set to max value TMR0IE = 0; // disable any more interrupts } // end if TMR0IF = 0; // clear event flag } // end if // Timer1 code if((TMR1IE)&&(TMR1IF)) { // timer1 has rolled over chlaCount = 65535; // set to max value TMR1IE = 0; // disable any more interrupts TMR1IF = 0; // clear event flag } // end if } // end isr()