;******************************************************************* ; TEMPALM4.ASM ; Temperature Alarm/Thermostat Celsius and Fahrenheit Display ; ; Use with Philips 2322-640-63103 NTC Thermistor R/r=9.0, 10K@25C ; ; Valid range of -50C to +125C. Basic accuracy 2% within the ; range -30C to +80C. ;******************************************************************* ; Target: PIC16C84 or PIC16F84 ; ; Hardware: ; Port B <> LTN211 Display and Keypad ; RB7 E : Enable (H->L transition latches data) ; RB6 KeyPad Input ; RB5 Piezo Beeper Output ; RB4 Register Select for LCD ; RB0 - RB3 LCD Data Lines and 4 keys ; ; Port A <> ADC0831 Serial ADC ; RA0 ADC Data (Input) ; RA1 ADC Clock (Output) ; RA2 ADC CS (Output) ; RA3 Thermostat Output (LED/Opto Driver) ; ;******************************************************************* ; LIST p=16F84 ;PIC16F84 is the target processor INCLUDE "P16F84.INC" ;Include file with register defines ; ;******************************************************************** ; Test Program ;********************************************************************* ;Register Defines Temp equ 2E ;temp storage during minus sign functions ADCresult equ 2D ;stores ADC reading ADCCtr equ 2C ;stores count for reading 8 bits from serial ADC MaxTemp equ 2B ;Temp. locations for Min and Max temp MinTemp equ 2A HighAlarm equ 29 ;Current high/low alarm values LowAlarm equ 28 ;Stored as ADC values, not actual temps. AlarmOn equ 27 Temp2 equ 26 ;temp storage ;Registers for B2_BCD H_Byte equ 19 ;Input (Binary) values L_Byte equ 1A R0 equ 1B ;Output (BCD) values R1 equ 1C R2 equ 1D count equ 1E ;Temp. registers for function B2temp equ 1F ;Registers for Misc. Functions DispChar equ 10 ;Character to display on LCD DelayTemp equ 11 ;Temp Counter for time delay DelayT2 equ 12 ;Counter for LONG time delay TempKey equ 13 ;Temporary key press value AlarmFlag equ 14 ;Bit1=ALARM_ACTIVE CharCounter equ 15 ;Counter for String printing DegreesC equ 16 ;Temperature in degrees Celsius DegreesSign equ 17 ;Sign Flag for degrees mulplr equ 18 ;Multiplier for 8*8 (C->F conversion) ;PORT defines ADCCLK equ 1 ADCDAT equ 0 ADCCS equ 2 LED equ 3 ;Alarm/Thermostat Output LED BEEPER equ 5 ;Beeper on Port B ;EEPROM addresses EEADR_HI_LIM equ 1 ;High temperature alarm/limit EEADR_LO_LIM equ 2 ;Low temperature alarm/limit EEADR_MAX_TEMP equ 3 ;Maximum temperature reached EEADR_MIN_TEMP equ 4 ;Minimum temperature reached EEADR_ALARM_ON equ 5 ;Alarm On/Off Status ;PIC Register Location Defines EEDATA equ 8 ;EEPROM register defines EEADR equ 9 EECON1 equ 88 EECON2 equ 89 ;Keys KEY_MODE equ 0 ;MODE key used to set parameters KEY_UP equ 1 ;Increment key KEY_DN equ 2 ;Decrement key KEY_ENTER equ 3 ;ENTER key ;Flags ALARM equ 1 ;Flag to Signify that Alarm is currently ON ON equ 1 ;Flag to enable Audible Alarm ;MAIN Program Begins goto main ;Celsius Conversion Table ; Parameters: ADC value in w ; Returns : Celsius temperature (signed via bit 7) in w CTable addwf PCL,f ;calculate jump table location retlw .50+80 ;location 0 - i.e. ADC reading of 0 retlw .50+80 ;Set BIT 7 for a negative quantity retlw .50+80 retlw .50+80 retlw .49+80 retlw .46+80 retlw .43+80 retlw .40+80 retlw .39+80 retlw .37+80 retlw .35+80 retlw .34+80 retlw .32+80 retlw .31+80 retlw .30+80 retlw .29+80 retlw .27+80 ;location 10h retlw .26+80 retlw .25+80 retlw .24+80 retlw .24+80 retlw .23+80 retlw .22+80 retlw .21+80 retlw .20+80 retlw .19+80 retlw .19+80 retlw .18+80 retlw .17+80 retlw .16+80 retlw .16+80 retlw .15+80 retlw .15+80 ;location 20h retlw .14+80 retlw .13+80 retlw .13+80 retlw .12+80 retlw .12+80 retlw .11+80 retlw .11+80 retlw .10+80 retlw .9+80 retlw .9+80 retlw .8+80 retlw .8+80 retlw .7+80 retlw .7+80 retlw .6+80 retlw .6+80 ;location 30 retlw .5+80 retlw .5+80 retlw .4+80 retlw .4+80 retlw .3+80 retlw .3+80 retlw .2+80 retlw .2+80 retlw .2+80 retlw .1+80 retlw .1+80 retlw .0 retlw .0 retlw .1 retlw .1 retlw .1 ;location 40 retlw .2 retlw .2 retlw .2 retlw .3 retlw .3 retlw .4 retlw .4 retlw .4 retlw .5 retlw .5 retlw .6 retlw .6 retlw .6 retlw .7 retlw .7 retlw .7 ;location 50 retlw .8 retlw .8 retlw .9 retlw .9 retlw .9 retlw .10 retlw .10 retlw .10 retlw .11 retlw .11 retlw .12 retlw .12 retlw .12 retlw .13 retlw .13 retlw .13 ;location 60 retlw .14 retlw .14 retlw .14 retlw .15 retlw .15 retlw .15 retlw .16 retlw .16 retlw .16 retlw .17 retlw .17 retlw .17 retlw .18 retlw .18 retlw .18 retlw .19 ;location 70 retlw .19 retlw .20 retlw .20 retlw .20 retlw .21 retlw .21 retlw .21 retlw .22 retlw .22 retlw .22 retlw .23 retlw .23 retlw .23 retlw .24 retlw .24 retlw .25 ;location 80 retlw .25 retlw .25 retlw .26 retlw .26 retlw .26 retlw .27 retlw .27 retlw .27 retlw .28 retlw .28 retlw .28 retlw .29 retlw .29 retlw .30 retlw .30 retlw .31 ;location 90 retlw .31 retlw .31 retlw .32 retlw .32 retlw .33 retlw .33 retlw .33 retlw .34 retlw .34 retlw .34 retlw .35 retlw .35 retlw .35 retlw .36 retlw .36 retlw .37 ;location A0 retlw .37 retlw .38 retlw .38 retlw .38 retlw .39 retlw .40 retlw .40 retlw .40 retlw .41 retlw .41 retlw .42 retlw .42 retlw .42 retlw .43 retlw .43 retlw .44 ;location B0 retlw .45 retlw .45 retlw .46 retlw .46 retlw .46 retlw .47 retlw .47 retlw .48 retlw .48 retlw .49 retlw .50 retlw .50 retlw .51 retlw .51 retlw .52 retlw .52 ;location C0 retlw .53 retlw .53 retlw .54 retlw .55 retlw .55 retlw .56 retlw .56 retlw .57 retlw .57 retlw .58 retlw .59 retlw .60 retlw .61 retlw .61 retlw .62 retlw .62 ;location D0 retlw .63 retlw .64 retlw .65 retlw .66 retlw .66 retlw .67 retlw .68 retlw .69 retlw .70 retlw .71 retlw .72 retlw .73 retlw .73 retlw .74 retlw .76 retlw .77 ;location E0 retlw .78 retlw .80 retlw .81 retlw .82 retlw .83 retlw .85 retlw .86 retlw .87 retlw .89 retlw .91 retlw .92 retlw .94 retlw .96 retlw .98 retlw .100 retlw .105 ;location F0 retlw .107 retlw .110 retlw .112 retlw .115 retlw .120 retlw .125 retlw .125 retlw .126 ;End of Table (F8) org 100 ;Put all string tables on Page 2 StringSetup addwf PCL,f ;Calculated jump for all strings StringInit retlw 'T' retlw 'e' retlw 'm' retlw 'p' retlw 'A' retlw 'l' retlw 'm' retlw '2' retlw ' ' retlw 'V' retlw '2' retlw '.' retlw '1' retlw 80 StringInit2 retlw 'M' retlw '.' retlw 'C' retlw 's' retlw 'e' retlw 'l' retlw 'e' retlw ' ' retlw '9' retlw '9' retlw '/' retlw '0' retlw '9' retlw 80 StringTemp retlw '_' retlw 'T' retlw 'e' retlw 'm' retlw 'p' retlw '=' retlw 80 ;End-of-string terminator StringMin retlw 'M' retlw 'i' retlw 'n' retlw ' ' retlw 'T' retlw '=' retlw 80 ;End-of-string terminator StringMax retlw 'M' retlw 'a' retlw 'x' retlw ' ' retlw 'T' retlw '=' retlw 80 ;End-of-string terminator StringHi retlw 'H' retlw 'i' retlw ' ' retlw 'L' retlw 'i' retlw 'm' retlw '=' retlw 80 ;End-of-string terminator StringLow retlw 'L' retlw 'o' retlw ' ' retlw 'L' retlw 'i' retlw 'm' retlw '=' retlw 80 ;End-of-string terminator StringSetLowAlarm retlw 'S' retlw 'e' retlw 't' retlw ' ' retlw 'L' retlw 'o' retlw 'w' retlw ' ' retlw 'L' retlw 'i' retlw 'm' retlw 'i' retlw 't' retlw 80 StringSetHighAlarm retlw 'S' retlw 'e' retlw 't' retlw ' ' retlw 'H' retlw 'i' retlw 'g' retlw 'h' retlw ' ' retlw 'L' retlw 'i' retlw 'm' retlw 'i' retlw 't' retlw 80 ;End-of-string terminator StringClearMinMax retlw 'C' retlw 'l' retlw 'e' retlw 'a' retlw 'r' retlw ' ' retlw 'M' retlw 'i' retlw 'n' retlw '/' retlw 'M' retlw 'a' retlw 'x' retlw '?' retlw 80 ;End-of-string terminator StringPressClr retlw 'P' retlw 'r' retlw 'e' retlw 's' retlw 's' retlw ' ' retlw '+' retlw ' ' retlw 't' retlw 'o' retlw ' ' retlw 'C' retlw 'l' retlw 'r' retlw 80 ;End-of-string terminator ;>>> Future Option: Alarm/Thermostat function StringSetAlarm retlw 'A' retlw 'l' retlw 'a' retlw 'r' retlw 'm' retlw ' ' retlw 'O' retlw 'n' retlw '/' retlw 'O' retlw 'f' retlw 'f' retlw '?' retlw 80 ;End-of-string terminator StringPressOn retlw 'P' retlw 'r' retlw 'e' retlw 's' retlw 's' retlw ' ' retlw '+' retlw ' ' retlw 'f' retlw 'o' retlw 'r' retlw ' ' retlw 'O' retlw 'N' retlw ' ' retlw 80 ;End-of-string terminator StringPressOff retlw 'P' retlw 'r' retlw 'e' retlw 's' retlw 's' retlw ' ' retlw '+' retlw ' ' retlw 'f' retlw 'o' retlw 'r' retlw ' ' retlw 'O' retlw 'F' retlw 'F' retlw 80 ;End-of-string terminator StringAlmDisabled retlw 'A' retlw 'l' retlw 'a' retlw 'r' retlw 'm' retlw ' ' retlw 'D' retlw 'i' retlw 's' retlw 'a' retlw 'b' retlw 'l' retlw 'e' retlw 'd' retlw 80 ;End-of-string terminator main clrf PORTB ;Make All Outputs LOW movlw b'01000000' ;Port B all outputs except Keypad input bsf STATUS,RP0 ;select Page 1 movwf TRISB bcf STATUS,RP0 ;select Page 0 clrf PORTB ;Make All Outputs LOW clrf PORTA ;Make All Outputs LOW movlw b'00000001' ;Port A all outputs except ADC Data inputs bsf STATUS,RP0 ;select Page 1 movwf TRISA bcf STATUS,RP0 ;select Page 0 movlw b'00000100' ;All Outputs LOW except ADC /CS high movwf PORTA bsf PORTB,BEEPER ;Wait for LCD to power-up and beep call Delay bcf PORTB,BEEPER call LCD_Init movlw StringInit ;Display Initialization Message call OutString call LCD_L2 movlw StringInit2 call OutString movlw .16 movwf Temp InitDly call LongDelay decfsz Temp,f goto InitDly ;Initialize parameters from on-chip EEPROM storage movlw EEADR_HI_LIM ;Initialize HIGH and LOW alarms from EEPROM call ReadEE ;W now contains High limit movwf HighAlarm movlw EEADR_LO_LIM call ReadEE movwf LowAlarm movlw EEADR_MIN_TEMP ;Initialize HIGH and LOW alarms from EEPROM call ReadEE movwf MinTemp movlw EEADR_MAX_TEMP call ReadEE movwf MaxTemp movlw EEADR_ALARM_ON call ReadEE movwf AlarmOn clrf AlarmFlag ;Set Alarm OFF mainloop call LCD_Cls ;Clear Display call ReadADC ;Update MIN and MAX temps if required movf MaxTemp,w subwf ADCresult,0 ;check if max temp exceeded btfss STATUS,C goto NotNewMax movf ADCresult,w ;ADC > Max temp ... update var as well as EEPROM movwf MaxTemp movwf Temp movlw EEADR_MAX_TEMP call WriteEE ;Write Max Temp to EEPROM NotNewMax movf MinTemp,w subwf ADCresult,0 ;check if under min temp btfsc STATUS,C goto NotNewMin movf ADCresult,w ;ADC < Min temp ... update var and EEPROM movwf MinTemp movwf Temp movlw EEADR_MIN_TEMP call WriteEE ;Write Min Temp to EEPROM NotNewMin ;Display current temperature movlw 80 ;Top Line movwf DispChar call LCD_Cmd movlw StringTemp ;Display "Temp=" call OutString movfw ADCresult ;Convert to degrees, display current temp and "C" call DisplayTemp movlw b'10001111' ;Top Line, last char movwf DispChar call LCD_Cmd movlw '_' movwf DispChar call LCD_Chr bcf AlarmFlag,ALARM ;Turn off alarm flag movf HighAlarm,w subwf ADCresult,0 ;check if high alarm exceeded btfsc STATUS,C goto AlarmIsOn movf LowAlarm,w subwf ADCresult,0 ;check if low alarm exceeded btfsc STATUS,C goto NoAlarm AlarmIsOn bsf AlarmFlag,ALARM ;set alarm flag ON NoAlarm ;Set or Clear limit LED as required btfsc AlarmFlag,1 ;Check if Alarm is ON, if so Light LED goto AlmLedOn bcf PORTA,LED ;LED Off goto AlmLedOff AlmLedOn bsf PORTA,LED AlmLedOff ;Display min/max and hi/low limits alternately on bottom movlw b'11000000' ;Bottom Line movwf DispChar call LCD_Cmd movlw StringMin ;Display "Min T=" call OutString movfw MinTemp call DisplayTemp call BeepAndTest ;Beep if alarm enabled and test keypad movlw b'11000000' ;Bottom Line movwf DispChar call LCD_Cmd movlw StringMax ;Display "Max=" call OutString movfw MaxTemp call DisplayTemp call BeepAndTest ;Beep if alarm enabled and test keypad ;Display High and Low Alarm Values movlw b'11000000' ;Bottom Line movwf DispChar call LCD_Cmd movlw StringHi ;Display "Hi=" High Alarm message call OutString movfw HighAlarm call DisplayTemp call BeepAndTest ;Beep if alarm enabled and test keypad movlw b'11000000' ;Bottom Line movwf DispChar call LCD_Cmd movlw StringLow ;Display "Lo=" Low Alarm message call OutString movfw LowAlarm call DisplayTemp call BeepAndTest ;If alarm is disabled, display warning message btfsc AlarmOn,ON ;Display warning only if alarm is disabled goto mainloop movlw b'11000000' ;Bottom Line movwf DispChar call LCD_Cmd movlw StringAlmDisabled ;Display "Alarm Disabled" call OutString call BeepAndTest goto mainloop ;End Of Main Loop ;### Called Functions ; BeepAndTest: If alarm is enabled, beep. Also check keypad for keypress during delay ; DisplayTemp: Converts an ADC value into degrees C and displays on LCD ; ScanKey : scans four keys, returns key pressed in w ;If alarm is enabled and Alarm limits are exceeded, beep. ;Also, check keypad for keys pressed BeepAndTest btfss AlarmOn,ON ;Beep only if Alarm is Enabled goto NoAudibleAlarm btfsc AlarmFlag,ALARM ;Check if Alarm is ON, if so, Beep 1 sec bsf PORTB,BEEPER NoAudibleAlarm movlw .8 ;Call 125mS delay 8 times for 1 second delay movwf Temp DDelay decfsz Temp,f goto DelayIt bcf PORTB,BEEPER ;Turn off beeper return ;Check Keypad for MODE key pressed. If pressed, Jump to Parameter Setting ;routine. Otherwise, just delay one second for display DelayIt call LongDelay ;125mS delay call ScanKey ;Check if a key is pressed movwf Temp2 btfsc Temp2,KEY_MODE ;Go to Parameter Setting mode call ModeSet goto DDelay ;### KeyPad Scan Function ;Returns either 0 in w (no key pressed) or bits 0-3 set in w for key pressed ;Fully debounced, waits for key release ScanKey call TestKey movwf Temp2 btfss Temp2,7 ;Is w still null? (i.e. is bit 7 still set) goto WaitForRls movlw 0 ;Nothing found, clear to return WaitForRls movwf TempKey WaitKeyLoop call TestKey movwf Temp2 btfss Temp2,7 ;Is w still null? (i.e. is bit 7 still set) goto WaitKeyLoop ;Key still down .... wait for release movfw TempKey ;Put Key Return Value into w return ;### KeyPad Non-debounced Scan Function ;Returns either 0 in w (no key pressed) or 1-4 in w for key pressed ;No debounce, active on key press ScanKey2 call TestKey movwf Temp2 btfss Temp2,7 ;Is w still null? (i.e. is bit 7 still set) return ;w must contain 1-4 movlw 0 ;Nothing found, clear to return ;Return bit 7 high if no key pressed or 1-4 in w for key pressed TestKey clrf PORTB ;All data lines low movlw 80 ;Pre-Load w with bit 7 high bsf PORTB,0 ;Make Key 1 row HIGH btfsc PORTB,6 ;Check if key 1 pressed movlw b'00000001' bcf PORTB,0 bsf PORTB,1 ;Make Key 2 row HIGH btfsc PORTB,6 ;Check if key 2 pressed movlw b'00000010' bcf PORTB,1 bsf PORTB,2 ;Make Key 3 row HIGH btfsc PORTB,6 ;Check if key 3 pressed movlw b'00000100' bcf PORTB,2 bsf PORTB,3 ;Make Key 4 row HIGH btfsc PORTB,6 ;Check if key 4 pressed movlw b'00001000' bcf PORTB,3 return ;### SET key was pressed ... Allow user to set parameters ModeSet call LCD_Cls movlw StringSetHighAlarm ;Display "SET HIGH ALARM" call OutString ModeSetHi2 movlw b'11000000' ;Bottom Line movwf DispChar call LCD_Cmd movlw StringHi ;Display "HI =" call OutString movf HighAlarm,w call DisplayTemp call ScanKey2 ;Check if a key is pressed movwf Temp2 btfsc Temp2,KEY_MODE ;If Key 1, go to next MODE (Set Low Alm) goto ModeSetLow btfsc Temp2,KEY_UP ;If "+", Increment HIGH alarm Value incf HighAlarm btfsc Temp2,KEY_DN ;If "-", Decrement HIGH alarm Value decf HighAlarm call ShortDelay goto ModeSetHi2 ModeSetLow call LCD_Cls movlw StringSetLowAlarm ;Display "SET LOW ALARM" call OutString ModeSetLow2 movlw b'11000000' ;Bottom Line movwf DispChar call LCD_Cmd movlw StringLow ;Display "LO =" call OutString movfw LowAlarm call DisplayTemp call ScanKey2 ;Check if a key is pressed movwf Temp2 btfsc Temp2,KEY_MODE ;If Key 1, go to next MODE (Clr Min/Max) goto ModeSetClr btfsc Temp2,KEY_UP ;If "+", Increment LOW alarm Value incf LowAlarm btfsc Temp2,KEY_DN ;If "-", Decrement LOW alarm Value decf LowAlarm call ShortDelay goto ModeSetLow2 ModeSetClr call LCD_Cls movlw StringClearMinMax ;Display "CLEAR MIN/MAX" call OutString ModeSetClr2 movlw b'11000000' ;Bottom Line movwf DispChar call LCD_Cmd movlw StringPressClr ;Display "PRESS + TO CLR" call OutString call ScanKey ;Check if a key is pressed movwf Temp2 btfsc Temp2,KEY_MODE ;If Key 1, go to next MODE (Done) goto ModeSetAlarmOn btfsc Temp2,KEY_UP ;If "+", Clear Min/Max value goto ClrMinMax call ShortDelay goto ModeSetClr2 ClrMinMax call ReadADC ;Initialize Min and Max temps to current movfw ADCresult movwf MaxTemp movwf MinTemp movwf Temp movlw EEADR_MIN_TEMP call WriteEE ;Update Min Temp in EEPROM movlw EEADR_MAX_TEMP call WriteEE ;Update Max temp in EEPROM ModeSetAlarmOn call LCD_Cls movlw StringSetAlarm ;Display "Alarm ON/OFF?" call OutString ModeSetAlarmOn2 movlw b'11000000' ;Bottom Line movwf DispChar call LCD_Cmd btfss AlarmOn,ON ;Display correct message goto ModeAlarmOn ModeAlarmOff ;Alarm is ON, allow user to turn OFF movlw StringPressOff ;Display "PRESS + FOR OFF" call OutString goto ModeAlarmMessageDone ModeAlarmOn ;Alarm is OFF, allow user to turn ON movlw StringPressOn ;Display "PRESS + FOR ON" call OutString ModeAlarmMessageDone call ScanKey ;Check if a key is pressed movwf Temp2 btfsc Temp2,KEY_MODE ;If Key 1, go to next MODE (Done) goto ModeSetDone btfsc Temp2,KEY_UP ;If "+", Toggle Alarm Status comf AlarmOn,f ;Complement to invert On/Off bit status call ShortDelay goto ModeSetAlarmOn2 ModeSetDone call ShortDelay movf HighAlarm,w ;Save updated HIGH and LOW alarms and Alarm Enable to EEPROM movwf Temp movlw EEADR_HI_LIM call WriteEE movf LowAlarm,w movwf Temp movlw EEADR_LO_LIM call WriteEE movf AlarmOn,w movwf Temp movlw EEADR_ALARM_ON call WriteEE return ;******************************************************************* ; Internal functions ;******************************************************************* ;OutString: Routine to print a string to the LCD ; Parameters: Pointer (address) of 0x80 terminated string ; Returns: Nothing ; Calls: LCD_Chr ; Vars Used: CharCounter, DispChar OutString movwf CharCounter decf CharCounter,f ;Real starting address of string NextChr ;Since all strings are in Page 1, load PCLATH now movlw 1 movwf PCLATH movf CharCounter,w call StringSetup movwf DispChar btfsc DispChar,7 return call LCD_Chr incf CharCounter goto NextChr ;ReadADC: Reads a byte from the ADC0831 ; Parameters: None ; Returns: One byte in ADCresult representing the ADC value ReadADC clrf ADCresult bcf PORTA,ADCCS ;Activate /CS line on the ADC to start movlw 8 ;Set number of bits to read in = 8 +1 start movwf ADCCtr ;Load this into the counter register bsf PORTA,ADCCLK ;Pulse the ADC clock line High then Low to nop ; signal the start of a conversion bcf PORTA,ADCCLK Get_One_Bit ;This is the main loop, should execute 9 times bsf PORTA,ADCCLK ;Pulse the ADC clock line high then low nop ; to get one data bit bcf PORTA,ADCCLK bcf STATUS,C ;Clear Carry Bit btfsc PORTA,ADCDAT ;Check the value of the data bit bsf STATUS,C ;Bit is a one ... set carry bit and rotate in rlf ADCresult ;Shift bits left from carry into ADResult decfsz ADCCtr,f ;Decrement Bit Counter goto Get_One_Bit ;Do it 9 times, first bit is a START bit bsf PORTA,ADCCS ;When done, Disable the ADC ;LIMIT max reading if necessary since table size < 255 bytes movlw .248 ;Limit reading of ADC to F8 to prevent subwf ADCresult,w ; going past last entry in jump table btfss STATUS,C return ;All is OK, just return with the value movlw .248 ;Limit the ADC reading at end of jump table movwf ADCresult return ;DisplayTemp: Converts an ADC reading to degrees C and degrees F ; and displays on LCD ; Parameters: ADC reading in W ; Returns: Nothing DisplayTemp clrf PCLATH ;Conversion table is in 1st page call CTable ;Goto jump table for Celsius Temperature movwf L_Byte ;Load binary data for BCD conversion movwf DegreesC ;Store for later use in conversion to degrees F bcf DegreesSign,0 ;Clear negative flag btfss L_Byte,7 ;Test bit 7 (is it a negative number?) goto NotNeg movlw '-' ;Negative number, display minus sign movwf DispChar call LCD_Chr bcf L_Byte,7 ;Convert to non-negative number bsf DegreesSign,0 ;Flag that this is a negative number for C->F bcf DegreesC,7 ;Convert to unsigned number NotNeg clrf H_Byte call B2_BCD ;convert to BCD ;Display R1 lo (LSB) as an ASCII digit movfw R1 andlw b'00001111' btfsc STATUS,Z ;Remove leading zeroes goto BlankOne addlw 30 ;Turn into an ASCII digit by adding 0x30 movwf DispChar call LCD_Chr BlankOne ;Display R2 hi then R2 lo swapf R2,0 andlw b'00001111' addlw 30 ;Turn into an ASCII digit movwf DispChar call LCD_Chr movfw R2 andlw b'00001111' addlw 30 ;Turn into an ASCII digit movwf DispChar call LCD_Chr movlw 'C' ;Display "C/" movwf DispChar call LCD_Chr movlw '/' movwf DispChar call LCD_Chr ;Convert degrees C to degrees F by multiplying by 29/16 and adding 32 movlw .29 movwf mulplr ;Multiply DegreesC * 29. 16-bit Result is is H_Byte, L_Byte mpy_S clrf H_Byte clrf L_Byte movlw 8 movwf count movf DegreesC,w bcf STATUS,C ; Clear the carry bit in the status Reg. mloop rrf mulplr,f btfsc STATUS,C addwf H_Byte,f rrf H_Byte,f rrf L_Byte,f decfsz count,f goto mloop ;Divide by 16 (29/16 is almost = 9/5) movlw 4 movwf count NextShift bcf STATUS,C rrf H_Byte,f rrf L_Byte,f decfsz count,f goto NextShift ;Convert to a 2's complement signed number then add 32 btfss DegreesSign,0 goto PositiveTemp ;Positive number, no need to convert comf L_Byte,f ;Complement and add 1 to convert to negative incf L_Byte,f ;an never exceed -.91 anyway comf H_Byte,f PositiveTemp movlw .32 addwf L_Byte,f btfsc STATUS,C ;L_Byte oveflowed, increment H_Byte incf H_Byte,f ;If Degrees F is a negative number, display it as such now btfss H_Byte,7 goto FDegNotNeg movlw '-' movwf DispChar call LCD_Chr clrf H_Byte ;Always zero since max=-50F comf L_Byte,f incf L_Byte,f FDegNotNeg call B2_BCD ;convert to BCD ;Display R1 lo (LSB) as an ASCII digit movfw R1 andlw b'00001111' btfsc STATUS,Z ;Remove leading zeroes goto BlankOneF addlw 30 ;Turn into an ASCII digit by adding 0x30 movwf DispChar call LCD_Chr BlankOneF ;Display R2 hi then R2 lo swapf R2,0 andlw b'00001111' addlw 30 ;Turn into an ASCII digit movwf DispChar call LCD_Chr movfw R2 andlw b'00001111' addlw 30 ;Turn into an ASCII digit movwf DispChar call LCD_Chr movlw 'F' ;Display "F" movwf DispChar call LCD_Chr movlw ' ' ;Trailing blanks to clear display movwf DispChar call LCD_Chr movlw ' ' movwf DispChar call LCD_Chr return ;ReadEE: Reads a byte from the EEPROM of the PIC16C84/16F84 ; Parameters: location in EEPROM (0-63 dec) in W ; Returns: byte read in W register ReadEE movwf EEADR ;Put desired address into EEADR bsf STATUS,RP0 ;Select Register Page 1 bsf EECON1,0 ;RD operation flag bcf STATUS,RP0 ;Select Register Page 0 again movf EEDATA,W ;Read data, put into W register return ;WriteEE: Writes a byte to the EEPROM of the PIC16C84/16F84 ; Parameters: location in EEPROM (0-63 dec) in W ; data to be written in register 'Temp' ; Note: Value in Temp is destroyed during write operation ; Disables interrupts during write WriteEE: movwf EEADR ;Put desired address into EEADR movf Temp,W ;Put data to be written into EEDATA movwf EEDATA movf INTCON,W ;Store old interrupt status in Temp movwf Temp bcf INTCON,7 ;Turn off all interrupts bsf STATUS,RP0 ;Select Register Page 1 bsf EECON1,2 ;Write Enable flag movlw 55h ;Required sequence to write to EEPROM movwf EECON2 movlw b'10101010' movwf EECON2 bsf EECON1,1 ;WR operation flag EEIsBusy btfsc EECON1,1 ;Wait for BUSY flag to end goto EEIsBusy bcf EECON1,2 ;Disable Write Enable flag bcf STATUS,RP0 ;Select Register Page 0 again movf Temp,w ;Reset interrupts to original state movwf INTCON return ;******************************************************************* ; LTN211 16 char by 2 LCD display functions for PICPROTO ;******************************************************************* LCD_Init ;Initialize LTN211 LCD display movlw 33 ;Output 0x33 to LCD movwf DispChar call LCD_Cmd movlw 32 ;Output 0x32 to LCD movwf DispChar call LCD_Cmd movlw 28 ;Output 0x28 to LCD movwf DispChar ; 4 bit mode call LCD_Cmd movlw 0C ;Output 0x0C to LCD movwf DispChar ; Display ON, Cursor&Blink Off call LCD_Cmd movlw 06 ;Output 0x06 to LCD movwf DispChar ; Entry Mode: AutoIncrement call LCD_Cmd call LCD_Cls return LCD_Cls ;Clear LCD display screen, home cursor movlw 01 ;Output 0x01 to LCD movwf DispChar ; Clear Display call LCD_Cmd movlw 02 ;Output 0x02 to LCD movwf DispChar ; Home Cursor call LCD_Cmd call Delay call Delay return LCD_L2 ;Set cursor to start of LCD line 2 movlw b'11000000' movwf DispChar ; Set Display Cursor to Line 2 call LCD_Cmd call Delay call Delay call Delay return LCD_Cmd ;Send a command to the LCD display swapf DispChar,0 ;Put upper nibble into lower of W andlw b'00001111' ;Mask off upper nibble movwf PORTB bsf PORTB,7 ;Toggle Enable HIGH then LOW again call Delay call Delay bcf PORTB,7 call Delay call Delay movfw DispChar ;send lower nibble to display andlw b'00001111' ;Mask off upper nibble movwf PORTB bsf PORTB,7 ;Toggle Enable HIGH then LOW again call Delay call Delay bcf PORTB,7 call Delay call Delay ;? return LCD_Chr ;Send a Character to the LCD display swapf DispChar,0 ;Put upper nibble into lower of W andlw b'00001111' ;Mask off upper nibble movwf PORTB bsf PORTB,4 ;Set bit 4 (Register Select) HIGH bsf PORTB,7 ;Toggle Enable HIGH then LOW again bcf PORTB,7 movfw DispChar ;send lower nibble to display andlw b'00001111' ;Mask off upper nibble movwf PORTB bsf PORTB,4 ;Set bit 4 (Register Select) HIGH bsf PORTB,7 ;Toggle Enable HIGH then LOW again bcf PORTB,7 call Delay call Delay ;? return LongDelay ;Approx. 125 mS delay movlw .255 movwf DelayT2 ldelaya call Delay decfsz DelayT2,1 goto ldelaya return ShortDelay ;Approx. 25 mS delay movlw .51 movwf DelayT2 sdelaya call Delay decfsz DelayT2,1 goto sdelaya return Delay ;0.6ms delay for LCD initialization movlw .250 ;Load Temp with constant for .3 ms movwf DelayTemp delaya decfsz DelayTemp,1 ;Dec until zero goto delaya movlw .250 ;Load Temp with constant for .3 ms movwf DelayTemp delayb decfsz DelayTemp,1 ;Dec until zero goto delayb return ;******************************************************************* ; Binary to BCD Converter ; ; Input: Two bytes of RAM; L_Byte, H_Byte ; Output: Three bytes of RAM; R0, R1, R2 ; ; Usage: Put value into L_Byte and H_Byte, call B2_BCD, result in ; R2 is LSD and R1 is MSD: Four digits (nibbles) in 2 bytes ; Lower 4 bits of LSD are least sig. digit, upper 4 are 2nd ; digit. ;******************************************************************* B2_BCD bcf STATUS,0 ;Clear carry bit movlw .16 movwf count ;Set counter to 16 clrf R0 clrf R1 clrf R2 loop16 rlf L_Byte rlf H_Byte rlf R2 rlf R1 rlf R0 decfsz count goto adjDEC RETLW 0 adjDEC movlw R2 movwf FSR call adjBCD movlw R1 movwf FSR call adjBCD movlw R0 movwf FSR call adjBCD goto loop16 adjBCD movlw 3 addwf 0,W movwf B2temp btfsc B2temp,3 ;Test if result > 7 movwf 0 movlw 30 addwf 0,w movwf B2temp btfsc B2temp,7 ;Test if result > 7 movwf 0 ;Save as MSD RETLW 0 ;******************************************************************* END