' Therm4.Bas - PICAXE-08M2 (Stable Code)
' Modified 9/22/2011 to enhance finetune routine w/ scaleup values
' Modified 9/09/2011 to add 4-Line LCD display
' Modified 7/10/2011 for PICAXE 08M2
'
' Illustrates an interface with an NTC thermistor.
' Original prototype by phanderson.com
' copyright, Peter H Anderson, Baltimore, MD, June, '05
'
' Measures voltage across the thermistor and uses a combination of table lookup
' and linear interpolation to calculate the temperature in degrees C.
'
' Enhancements by M. Burnette for 08M2 and LCD code & clean-up
' copyright, Mickey R Burnette, Lawrenceville, GA, September 2011
' 929 Bytes / 2048
'
' WIRING:
' NTC is grounded on one side and 10K is used as a pull-up to +5.
' ADC is at junction, PIN #3 on PICAXE 08M2
'
#picaxe 08m2
#Terminal off
#freq m4
'#no_data ' REMARK THIS LINE for First Time programming of uC!
' The default power-up operating frequency is 4MHz
' LCD is on port C.1 which is 08M2 physical PIN #6
' PIN #7 port C.0 commonly used for SerTxD is NOT used in this project
SYMBOL DigitC = B0
SYMBOL WholeC = B1 ' ADVal not needed when TC_100 is calculated
SYMBOL ADValHi8 = B2
SYMBOL ADValLow2 = B3
SYMBOL N = B4
SYMBOL SignFlag = B4 ' N is not need when this is used
SYMBOL Diff = B5
SYMBOL DigitF = B5 ' Diff not needed when this is used
SYMBOL WholeF = B6
SYMBOL Fract = B7
SYMBOL COMMAND = B8
SYMBOL WholeH = B9
SYMBOL DigitH = B10
SYMBOL Sign = B11
SYMBOL WholeL = B12
SYMBOL DigitL = B13
SYMBOL ChangeMe14 = B14
SYMBOL ChangeMe15 = B15
SYMBOL Adjustment = B16
SYMBOL AdjMajor = B17
'SYMBOL table - aliases for word values
SYMBOL SetPoint = W9
SYMBOL ADVal = W10
SYMBOL TC_100 = W10
SYMBOL TempC = W11
SYMBOL TempHigh = W12
SYMBOL TempLow = W13
'
SYMBOL CLOCK = m4 ' Default 4MHz
SYMBOL BAUD = N4800_4 ' For use with modified (OPEN J3) DataVision LCD
'Note to self: serout on C.0 gives really weird results... eats characters
SYMBOL MONITOR = C.1 ' RS232 output on this pin
' Setup frequency for internal resonator
SetFreq CLOCK
' Initialize Dual 2-line LCD Display
COMMAND = 0 : GoSub DataVision
'Initialize low temperature history
TempLow = 65535
' Bytes 254 & 255 in EEPROM hold SetPoint factor (little endian)
Read 254, WORD SetPoint
'Enable C.3 pullup
Pullup %001000 ' If grounded, enter EEPROM/Temperature adjustment mode
Pause 500
IF PINC.3 = 0 Then FineTune
'
' _______________________ Main Routines Follow _____________________
Top:
GoSub MeasTemp
If TC_100 = $7fff Then
COMMAND = 2 : GoSub DataVision
serout MONITOR,BAUD,("Out of Range !!!")
ELSE
GoSub CalcTemp
GoSub UpdateLCD_T
GoSub UpdateLCD_L
EndIF
Pause 5000
Goto Top
MeasTemp:
ReadADC10 C.4, ADVal
ADValHi8 = ADVal / 4 ' isolate the high 8 bits
ADValLow2 = ADVal & $03 ' low two bits
' Default= 10542 from Peter's calculations
' EEPROM default 10512 based on 1% in test circuit
TC_100 = SetPoint
' Lookup table range is limited
If ADValHi8 < 16 OR ADValHi8 > 251 Then ' Out of Range
TC_100 = $7fff
End If
For N = 0 to ADValHi8 ' continue to subtract (walk the table)
Read N, Diff
TC_100 = TC_100 - Diff
Next
' Now for the low two bits, a linear interpolation
N = N + 1
Read N, Diff
Diff = Diff / 4 * ADValLow2
TC_100 = TC_100 - Diff
RETURN
CalcTemp:
SignFlag = TC_100 / 256 / 128
If SignFlag = 0 Then
Sign = " "
GoTo Positive
Else
TC_100 = TC_100 ^ $ffff + 1 ' twos comp
Sign = "-"
EndIf
Positive:
' Celsius display
TempC = TC_100
WholeC = TempC / 100
Fract = TC_100 % 100
DigitC = Fract / 10 'WholeC "." DigitC
' C --> F conversion
TC_100 = TC_100 * 9 / 5 + 3200
'
' Farenheit display
WholeF = TC_100 / 100
Fract = TC_100 % 100
DigitF = Fract / 10 'WholeF "." DigitF
'Digit = Fract % 10
'
' Perform high history for Farenheit
IF TC_100 > TempHigh Then
TempHigh = TC_100
EndIF
'
' High display
WholeH = TempHigh / 100
Fract = TempHigh % 100
DigitH = Fract / 10 'WholeH "." DigitH
'
' Perform low history for Farenheit
IF TC_100 < TempLow Then
TempLow = TC_100
EndIF
'
' Low display
WholeL = TempLow / 100
Fract = TempLow % 100
DigitL = Fract / 10 'WholeL "." DigitL
RETURN
DataVision: ' LCD stuff for Data Vision Dual 2x16 display Firmware 16215-1 S2RB Philco P345A
;COMMAND = 0 ' CLEAR ALL 4 LINES
;COMMAND = 1 ' GOTO Top Display
;COMMAND = 2 ' CLEAR Top Display
;COMMAND = 3 ' GOTO Lower Display
;COMMAND = 4 ' CLEAR Lower Display
;COMMAND = 5 ' Split-Line Filler Characters (16 spaces)
;COMMAND = 6 ' Lower Display OFF
;COMMAND = 7 ' Lower Display ON
;COMMAND = 8 ' Home without Clearing Top
;COMMAND = 9 ' Home without Clearing Lower
Select Case COMMAND
Case 0
GoSub ClearTop
GoSub ClearBottom
Case 1
serout MONITOR,BAUD,($12)
Case 2
GoSub ClearTop
Case 3
serout MONITOR,BAUD,($16)
Case 4
GoSub ClearBottom
Case 5
serout MONITOR,BAUD,(" ")
Case 6
serout MONITOR,BAUD,(%00010101,%00001010)
Case 7
serout MONITOR,BAUD,(%00010101,%00001100)
Case 8
serout MONITOR,BAUD,(%00010001,%10000000)
Case 9
serout MONITOR,BAUD,(%00010101,%10000000)
End Select
RETURN
ClearTop:
serout MONITOR,BAUD,(%00010001,%00000001)'Upper HOME+CLEAR L1 ")
RETURN
ClearBottom:
serout MONITOR,BAUD,(%00010101,%00000001)'Lower HOME+CLEAR L1 ")
RETURN
UpdateLCD_T:
COMMAND = 8 : GoSub DataVision ' Home Top
COMMAND = 1 : GoSub DataVision ' Select Top
IF WholeC < 10 then
serout MONITOR,BAUD,(" ",Sign,#WholeC,".",#DigitC," Celsius")
ELSE
serout MONITOR,BAUD,(Sign,#WholeC,".",#DigitC," Celsius")
EndIF
COMMAND = 5 : GoSub DataVision ' Spacer
serout MONITOR,BAUD,(" ",#WholeF,".",#DigitF," Farenheit")
RETURN
'
UpdateLCD_L:
COMMAND = 9 : GoSub DataVision ' Home Lower
COMMAND = 3 : GoSub DataVision ' Select Lower
IF WholeH < 10 then
serout MONITOR,BAUD,(" ",#WholeH,".",#DigitH," Record Hi")
ELSE
serout MONITOR,BAUD,(" ",#WholeH,".",#DigitH," Record Hi")
EndIF
COMMAND = 5 : GoSub DataVision ' Spacer
serout MONITOR,BAUD,(" ",#WholeL,".",#DigitL," Record Lo")
RETURN
FineTune:
' The wiper of a 10K pot is connected to C.2 and the other ends are +5 & GND
' The wiper is adjusted until the correct temperature is displayed and the jumper
' GNDing PINC.3 is removed to lock-in and write the correction factor to EEPROM
COMMAND = 4 : GoSub DataVision
COMMAND = 3 : GoSub DataVision
serout MONITOR,BAUD,(">> Tune MODE << ")
COMMAND = 5 : GoSub DataVision
serout MONITOR,BAUD,("(+/-): ",#Adjustment)
ReadADC C.2, Adjustment ' New Low Byte
' If the pot is at extremes for 10 seconds (5 loops) then Inc/Dec the HighByte
If Adjustment = 0 or Adjustment = 255 then
INC AdjMajor
Else
AdjMajor = 0
EndIf
If AdjMajor = 5 then
SetPoint = SetPoint / 256
Select case Adjustment
Case 0
DEC SetPoint
Case 255
INC SetPoint
End Select
SetPoint = SetPoint * 256
AdjMajor = 0
EndIf
SetPoint = SetPoint / 256 ' High Byte
SetPoint = SetPoint * 256 + Adjustment ' New Word Value
GoSub MeasTemp
GoSub CalcTemp
GoSub UpdateLCD_T
Pause 2000
IF PINC.3 = 0 Then FineTune
Write 254, WORD SetPoint ' Little endian
COMMAND = 4 : GoSub DataVision
COMMAND = 3 : GoSub DataVision
serout MONITOR,BAUD,(">> UPDATED !!<< ")
COMMAND = 5 : GoSub DataVision
serout MONITOR,BAUD,("Reboot in 2 sec.")
Pause 2000
RESET
' REMEMBER TO REMARK THE NO_DATA COMPILER DIRECTIVE ON FIRST PROGRAMMING
' EEPROM locations 0 - 15 not used for temperature scaling
' EEPROM loc 254 and loc 255 are for calibration Lo:Hi bytes
EEPROM 0, (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)
EEPROM 16, (254, 236, 220, 206, 194, 183, 173, 164)
EEPROM 24, (157, 149, 143, 137, 131, 126, 122, 117)
EEPROM 32, (113, 110, 106, 103, 100, 97, 94, 92)
EEPROM 40, (89, 87, 85, 83, 81, 79, 77, 76)
EEPROM 48, (74, 73, 71, 70, 69, 67, 66, 65)
EEPROM 56, (64, 63, 62, 61, 60, 59, 58, 57)
EEPROM 64, (57, 56, 55, 54, 54, 53, 52, 52)
EEPROM 72, (51, 51, 50, 49, 49, 48, 48, 47)
EEPROM 80, (47, 46, 46, 46, 45, 45, 44, 44)
EEPROM 88, (44, 43, 43, 43, 42, 42, 42, 41)
EEPROM 96, (41, 41, 41, 40, 40, 40, 40, 39)
EEPROM 104, (39, 39, 39, 39, 38, 38, 38, 38)
EEPROM 112, (38, 38, 37, 37, 37, 37, 37, 37)
EEPROM 120, (37, 36, 36, 36, 36, 36, 36, 36)
EEPROM 128, (36, 36, 36, 36, 36, 35, 35, 35)
EEPROM 136, (35, 35, 35, 35, 35, 35, 35, 35)
EEPROM 144, (35, 35, 35, 35, 35, 35, 35, 35)
EEPROM 152, (35, 35, 35, 35, 35, 35, 35, 35)
EEPROM 160, (36, 36, 36, 36, 36, 36, 36, 36)
EEPROM 168, (36, 36, 36, 37, 37, 37, 37, 37)
EEPROM 176, (37, 37, 38, 38, 38, 38, 38, 39)
EEPROM 184, (39, 39, 39, 39, 40, 40, 40, 41)
EEPROM 192, (41, 41, 42, 42, 42, 43, 43, 43)
EEPROM 200, (44, 44, 45, 45, 46, 46, 47, 47)
EEPROM 208, (48, 48, 49, 50, 50, 51, 52, 53)
EEPROM 216, (53, 54, 55, 56, 57, 58, 59, 61)
EEPROM 224, (62, 63, 65, 66, 68, 70, 72, 74)
EEPROM 232, (76, 78, 81, 84, 87, 90, 94, 98)
EEPROM 240, (102, 107, 113, 119, 126, 135, 144, 156)
EEPROM 248, (170, 187, 208, 235,0, 0, 16, 41)
