' Name : VMETERX4.pbp ' Compiler : PICBASIC PRO Compiler 2.6 ' Assembler : PM or MPASM ' Target PIC : PIC12F683 ' Hardware : LAB-X4 Experimenter Board ' Oscillator : 4MHz internal ' Keywords : ADCIN, SEROUT2 ' Description : PICBASIC PRO program to measure voltage (0-5VDC) and ' display on LCD with 2 decimal places. This program uses the */ operator ' to scale the ADC result from 0-1023 to 0-500. The */ performs a divide ' by 256 automatically, allowing math which would normally exceed the limit ' of a word variable. Connect analog input to channel-3 (RA4). ' ' Define ADCIN parameters Define ADC_BITS 10 ' Set number of bits in result Define ADC_CLOCK 3 ' Set clock source (3=rc) Define ADC_SAMPLEUS 50 ' Set sampling time in uS LCD Var GPIO.1 ' LCD TX pin T2400 Con 396 ' 2400 baud, true adval Var Word ' Create adval to store result ADCON0.7 = 1 ' Right justify result ANSEL = %00001000 ' Set AN3 analog, rest digital CMCON0 = 7 ' Analog comparators off Pause 500 ' Wait .5 second for LCD to init mainloop: ADCIN 3, adval ' Read channel 3 to adval (0-1023) adval = (adval */ 500)>>2 ' Equates to: (adval * 500)/1024 Serout2 LCD, T2400, [$fe, 1] ' Clear screen Serout2 LCD, T2400, ["DC Volts= ", DEC (adval/100), ".", DEC2 adval] ' Display the decimal value Pause 100 ' Wait .1 second Goto mainloop ' Do it forever End