Code:
'****************************************************************
'* Name : TempCont.pbp *
'* Author : Barry Phillips *
'* Notice : Copyright (c) 2012 Baztronics *
'* : All Rights Reserved *
'* Date : 16/12/2012 *
'* Version : 1.0 *
'* Notes : Temperature Controlled Switch *
'* : *
'****************************************************************
' PicBasic Pro program to display temperature from LM35DZ with
' 10-bit A/D conversion on LCD using PIC16F684 and switch relay on
' if ambient temperature is greater than temperature setting.
'
' LM35DZ output is 10mV per degree celcius
'
' 10-bit ADC equates to 4.88mV per step. For this application total accuracy
' has been forgone for simplicity and it is assumed that 1 step equates to
' 5mV or 0.5 degree celcius. The displayed temperature is calculated by
' ADCIN value multiplied by 5 (Adval*5).
'
' Connect LM35DZ to RA0 (Pin 13)
' Connect switch "Up" to RA3 (Pin 4) 10k Pull-Up to +5V
' Connect switch "Down" to RA4 (Pin 3) 10k Pull-Up to +5V
' Connect switch "Bypass" to RA5 (Pin 2) 10k Pull-Up to +5V
' Connect LED to RC5 (Pin 5) via 470R to +5V
' Connect Relay drive to RC4 (Pin 6)
' Connect LCD D4 to RC0 (Pin 10)
' Connect LCD D5 to RC1 (Pin 9)
' Connect LCD D6 to RC2 (Pin 8)
' Connect LCD D7 to RC3 (Pin 7)
' Connect LCD R/S to RA1 (Pin 12)
' Connect LCD E to RA2 (Pin 11)
' Define LCD registers and bits
Define LCD_DREG PORTC
Define LCD_DBIT 0
Define LCD_RSREG PORTA
Define LCD_RSBIT 1
Define LCD_EREG PORTA
Define LCD_EBIT 2
Define LCD_BITS 4
Define LCD_LINES 2
CMCON0 = %00000111 ' Disable comparators
ANSEL = %00000001 ' Set AN0 as analogue input
TRISA = %00111001 ' Set PORTA.0, PORTA.3 - .5 to input, all others output
TRISC = 0 ' Set PORTC as output
high PORTC.5 ' Ensure LED turned off
low PORTC.4 ' Ensure Relay is turned off
ADCON1 = %01010000 ' Set A/D clock Fosc/16
ADCON0 = %10000001 ' Right justify result
' Set Vref = Vdd
' Select channel AN0
' Turn on A/D converter
OSCCON = %01110001 ' Set clock frequency to 8MHz
define OSC 8
' 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
Pause 100 ' Wait 0.1 second
' Set up variables
adval var word 'ADCIN variable
Temp var word 'Temperature variable
Tempset var word 'Temperature setting variable
avecount var word 'Temperature average counter
tempsum var word 'Temperature averaging variable
B4 var byte 'Bypass flag
Tempup var PORTA.4 'Define Tempup switch port
Tempdown var PORTA.3 'Define Tempdown switch port
Bypass var PORTA.5 'Define Bypass switch port
LED1 var PORTC.5 'Define LED port output
Relay var PORTC.4 'Define Relay port output
DATA @1, 50 'Store 50 in EEPROM location 1
READ 1, Tempset 'Read EEPROM location 1 and save to Tempset
B4 = 0 'Reset bypass flag
high LED1 'Ensure LED is off
low Relay 'Ensure Relay is off
Lcdout $fe, 1 'Clear LCD
LCDOUT $FE, $80, " BAZTRONICS"
LCDOUT $FE, $C0, "TEMP. CONTROLLER"
pause 3000 'Pause 3 seconds
LCDOUT $FE, 1 'Clear LCD
Again:
avecount = 1 'Reset averaging counter
tempsum = 0 'Reset averaging variable
while avecount<1001 'Loop 1000 times
ADCIN 0, adval 'Read channel 0 to adval
tempsum = tempsum + adval 'sum temp average reading
avecount = avecount + 1 'Increment counter
if Bypass = 0 then manual 'Poll Bypass switch
If B4 = 0 then 'If Bypass not activated
if Tempup = 0 then Upstep 'Poll "Up" switch
if Tempdown = 0 then Downstep 'Poll "Down" switch
endif
wend
Temp = tempsum/200
Lcdout $FE, $80
LCDOUT " Temp: ", DEC Temp/10, ".", DEC1 Temp,$DF, "C "'Display Temp
If B4 = 1 then 'Test Bypass flag status
goto Again
Else
LCDOUT $FE, $C0+1 'Move cursor to beginning of second line
lcdout " Set: ", dec tempset/2, ".", dec1 tempset*5,$DF, "C "'Display Tempset
endif
If temp>tempset*5 then 'Test ambient temperature vs temperature setting
low LED1 'Turn on LED
high Relay 'Turn on relay
LCDOUT $FE, $C0, $DB
endif
if Temp < (tempset-2)*5 then'Test ambient temperature vs temperature setting
high LED1 'Turn off LED
low Relay 'Turn off relay
LCDOUT $FE, $C0, " "
endif
Goto Again 'Do it forever
Upstep:
If Tempset<99 then
Tempset = Tempset + 1 'Increment temperature setting
else
Tempset = Tempset 'Set Tempset upper limit
endif
LCDOUT $FE, $C0+1 'Move cursor to beginning of second line
lcdout " Set: ", dec tempset/2, ".", dec1 tempset*5,$DF,"C "'Display Tempset
WRITE 1, Tempset 'Store new Tempset to EEPROM location 1
Pause 250 'Pause 250ms for switch debounce
goto Again
Downstep:
if Tempset>2 then
Tempset = Tempset - 1 'Decrement temperature setting
else
Tempset = Tempset 'Set Tempset lower limit
endif
LCDOUT $FE, $C0+1 'Move cursor to beginning of second line
lcdout " Set: ", dec tempset/2, ".", dec1 tempset*5,$DF, "C "'Display Tempset
WRITE 1, Tempset 'Store new Tempset to EEPROM location 1
pause 250 'Pause 250ms for switch debounce
goto again
Manual:
If B4 = 0 then
B4 = 1 'Set Bypass flag
low LED1 'Turn on LED
high Relay 'Turn on Relay
LCDOUT $FE, $C0+1 ' Move cursor to beginning of second line
lcdout " BYPASS MODE " 'Display Bypass Mode message
else
B4 = 0 'Reset Bypass flag
high LED1 'Turn off LED
low Relay 'Turn off Relay
LCDOUT $FE, $C0+1 'Move cursor to beginning of second line
lcdout " Set: ", dec tempset/2, ".", dec1 tempset*5,$DF, "C "'Display Tempset
endif
Pause 250 'Pause 250ms for switch debounce
do while Bypass = 0 'Loop until Bypass switch is released
Loop
goto again
End
Any assistance would be greatly appreciated.
Help needed with ADCIN Averaging Routine
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