'ver 1.2 of a program for the Basic Smart A/C Controller
'uses a Picaxe-28x1 MCU, 
'2-74HC595 that drive two 7-segment com anode LED displays
'thermostat can be set from 35f to 85f
'to set thermostat, press up or down buttons display will flash at .5 htz
'use up down button to set--display returns to normal mode after 10 seconds
'compressor 5 minute off protection
'mode switch allows airflow to be displayed in .5f differential
'leds show compressor on, low airflow, ice on evaporator
'low airflow cutoff can be set by first putting mode switch in airflow
'position (pin 6 low) and MODE=0,AIRFLOW will then be displayed
'next, press up or down buttons and display will flash, then set airflow
'cutoff point.  when done, display will stop flashing and airflow cutoff 
'point will be set, mode switch can then be returned to normal
'normal comp off=5 minutes: with jumper at j6 it is 3 min
'6/23/2008 
	
	symbol	compon=7
	symbol	lowairflow=6
	symbol	iceonevap=5
	symbol	up=pin6
	symbol	down=pin5
	symbol	mode=pin7	'if airflow switch on mode=0, otherwise mode=1
	symbol	rcklatch=0	'setup out0(21) to 595 rck pin 12--latch
	symbol	sckclk=1	'setup out1(22) to 595 sck pin 11--clock
	symbol	ser=2		'setup out2(23) to 595 ser pin 14--ser in
	symbol	number=w13
	symbol	sum=w12
	symbol	adc10tempdata=w11
	symbol	RawTempData=w10
	symbol	AvgTemp=w9
	symbol	settemp=w8
	symbol	evapuhtmp=w7
	symbol	evaphtmp=w6
	symbol	airflow=w5
	symbol	setair=w4
	symbol	N=b0
	symbol	bitcounter=b1
	symbol	outbyte=b2
	symbol	outnible=b3
	symbol	whichsensor=b4
	symbol	room=0
	symbol	evap=1
	symbol	hevap=2
	symbol	tempscale=pin0 'dipsw1 pos 1 off deg F, on (pin0=0)deg C 
	symbol	celsius=0
	EEPROM 0,(18)
	EEPROM 2,(45)
	
	#picaxe 28x1
	
	start:disablebod
		low 	compon		'make sure compressor is off
		low 	lowairflow		'shut off law airflow LED
		low	iceonevap		'shut off Ice On Evaporator LED
		pause	2000			'wait two seconds
		high 	lowairflow		'turn on low airflow LED for test
		pause	2000
		low	lowairflow		'turn off lowairflow LED-test over
		high	iceonevap		'turn on Ice On Evap LED for init test
		pause	2000
		low	iceonevap		'turn off Ice on Evap LED-init test over
		'settemp=45
		'setair=18
		If tempscale=celsius then goto mainC 'check celsius of fahrenheit
		'if fahrenheit continue otherwise restart at mainC
	' Nextdisplay room temperature
	mainF:disablebod
		read 0, WORD setair
		read 2, WORD settemp
		pause 100 
		if mode=0 then 
			low compon
			gosub disairflow
		endif
		whichsensor=room		'choose room to take temp
		gosub	taketemp		'take room temperature
		number = AvgTemp/2 min 0 max 99 'number now has room temp in whole degf
		gosub	displnum		'display room temperature
		gosub evapsnsrs
		if up=0 or down=0 then gosub settherm
		whichsensor=room
		gosub	taketemp
		number=AvgTemp/2if number > settemp and airflow < setair and evapuhtmp > 64 then				high compon			'then send signal to turn on comp
		else					'else turn of compressor or
			low compon			'make sure it is off
		endif
		
		if airflow>=setair then 
			high lowairflow
		else
			low lowairflow
		endif
		if evapuhtmp<=64 then
			high iceonevap
			else low iceonevap
			endif
			
			goto mainF
	mainC: number=$FE
		gosub displnum
		pause 1000
		
		read 0, WORD setair
		read 2, WORD settemp
		pause 200 
		if mode=0 then 
			low compon
			gosub disairflow
		endif
	
		whichsensor=room		'choose room to take temp
		gosub	taketemp		'take room temperature
		number = AvgTemp/2 min 0 max 99 'number now has room temp in whole degf
		gosub	displnum		'display room temperature
		pause 2000
		gosub evapsnsrs
		if up=0 or down=0 then gosub settherm
		whichsensor=room
		gosub	taketemp
		number=AvgTemp/2
		sum=0
		For N=1 to 64
			readadc10 evap, RawTempData
			sum=sum + RawTempData
		Next N
			AvgTemp=Sum/64 min 0 max 198
		if number > settemp and airflow < setair and AvgTemp > 155 then					high compon				'then send signal to turn on comp
		else					'else turn of compressor or
			low compon			'make sure it is off
		endif
		
		if airflow>=setair then 
			high lowairflow
		else
			low lowairflow
		endif
		if AvgTemp<=155 then
			high iceonevap
			else low iceonevap
			endif
			
			goto mainC
	'***********************************
	'**subroutine to set the low airflow cutoff point
	setairflow:	read 0, WORD setair
			number=setair	'the next 6 lines
						'flash the airflow setting
		for N = 1 to 20
			number=setair	'the next 6 lines
			gosub displnum
			pause 125
			number=$FF		'shuts off
			gosub displnum 		'display for
			pause 125		'half second
		if up = 0 then
			inc setair
			pause 50
			N = 1
		elseif down=0 then
			dec setair
			pause 50
			N = 1
	 	endif
		next N
		write 0, WORD setair
		pause 500
		read 0, WORD setair 	  
		return
	'*************************************
	'**subroutine**Take 10 bit temperature data and store it in AvgTemp... 
	'whichsensor stores the info on which sensor is beign used
	'the variable RawTempData stores the info--in .5F resolution
	'thus if RawTempData=150 then the actual temp is 75F
	taketemp:		sum=0
		For N=1 to 64
			readadc10 whichsensor, RawTempData
			sum=sum + RawTempData
		Next N
			AvgTemp=Sum/64 min 0 max 198
		If tempscale=celsius then 
		AvgTemp=AvgTemp-64*5/9
		endif
		return
	'***************************************
	'this modified subroutine skips the celsius conversion
	'so airflow subroutine works better
	taketempC:		sum=0
		For N=1 to 64
			readadc10 whichsensor, RawTempData
			sum=sum + RawTempData
		Next N
			AvgTemp=Sum/64 min 0 max 198
		
		return
	
	'**subroutine**displays the data in "number" in decimal
	
	displnum:	
			if number = $FF then 'display 2 blanks if number =$FF
			 outnible = 10
			 gosub outdigit
			 outnible = 10
			 gosub outdigit
 			 pulsout rcklatch, 1
 			 return
			endif
			if number = $FE then 'display blank C" if number = $FE
				outnible = 11
				gosub outdigit
				outnible = 10
				gosub outdigit
				pulsout rcklatch, 1
			return
			endif
			
			outnible=number % 10	'outnible now has lsd
			gosub	outdigit		'send lsd
			outnible=number / 10	'outnible now has msd
			gosub outdigit
			pause 200
			pulsout rcklatch, 1
			return
			
			'next is outdigit routine


outdigit: '         	0    1    2    3    4    5    6    7    8    9  blank  C
lookup outnible, ($C0, $F9, $A4, $B0, $99, $92, $83, $F8, $80, $90, $FF, $46), outbyte

			for bitcounter = 0 to 7
			if outbyte>=128 then outhi
			low ser
			goto clkout
	outhi:	high ser
	clkout:	pulsout sckclk, 1
			outbyte=outbyte*2
		next bitcounter
return
	'**********************************************
	'the following subroutine displays the settemp and then flashes it
	'it also prepares for the set temperature to be changed with the
	'use of the up and down buttons
	settherm:   read 2, WORD settemp
			number=settemp	'the next 6 lines
						'flash the thermostat setting
		for N = 1 to 20
			number=settemp	'the next 6 lines
			'if tempscale=celsius then
			'number=number-64*5/9
			'endif
			gosub displnum
			pause 125
			number=$FF		'shuts off
			gosub displnum 	'display for
			pause 125		'half second
		if up = 0 then
			inc settemp
			pause 50
			N = 1
		elseif down=0 then
			dec settemp
			pause 50
			N = 1
	 	endif
		next N
		write 2, WORD settemp
		pause 500
		read 2, WORD settemp
		return

	'*******************************************
	'the following subroutine will display the
	'difference between the evaporator's 
	'heated and unheated sensors
	'this difference will be in half degrees
	'example if the display shows 20 this means
	'there is 10F degrees difference between sensors

	
	disairflow:			do
			gosub evapsnsrs
			number=airflow 
			gosub displnum
			pause 100
			if up=0 or down=0 then gosub setairflow
			loop until mode = 1
		return
	'********************************************
'subroutine takes tmp of both evap sensors (heated and unheated)
'and stores then in evaphtmps and evapuhtmp

	evapsnsrs:	whichsensor=evap	'first take the temp of unheated sensor
			gosub taketempC	'get data in AvgTemp
			evapuhtmp=AvgTemp
			whichsensor=hevap
			gosub taketempC
			evaphtmp=AvgTemp
			airflow=evaphtmp-evapuhtmp min 2 max 95
			return