Re: Thermo 7 segments - little problem
OK, I will follow Your advice ...
This is the last attempt, not-working (just "000" on display). Already feel like I came out of patience with this problem.
Code:' Pulse counter - attempt to converted for LED display termometer ' ============= ' ' File name : Count_Display.bas ' Company : Mister E ' Programmer : Steve Monfette ' Date : 27/12/2004 ' Device : PIC16F628A ' ' ' This program display to 3 x 7 segments dislay the result of ' pulses count on PORTA.4 pin/sec. ' ' Hardware connection : ' --------------------- ' 1. 3 X 7 segments display on PORTB<7:0> ' 2. 3 X PNP transistor on PORTA<3:0> to drive common anode ' of each 7 segments display ' ' ' Programming mode and PIC define ' ------------------------------- ' ;@ __config _HS_OSC & _WDT_ON & _PWRTE_ON & _LVP_OFF CMCON=7 ' ADDED FOR PIC16F628A DEFINE OSC 20 ' use 20 MHZ oscillator ' I/O Definition ' -------------- ' TRISA = %11111000 ' PORTA : <2:0> outputs to common Anode of 7 segment ' 1. PORTA.0 More significant ' 2. PORTA.2 Less significant ' : PORTA.4 input for signal ' TRISB = 0 ' PORTB connected to 7 segments ' B0 : segment a ' B1 : segment b ' B2 : segment c ' B3 : segment d ' B4 : segment e ' B5 : segment f ' B6 : segment g ' B7 : segment decimal dot ' Internal EEPROM definition ' -------------------------- ' data @0,192,249,164,176,153,146,130,248,128,144 ' table to convert ' numbers to 7 segments ' pattern output when ' drive invert ' Interrupt and register definition ' --------------------------------- OPTION_REG = %1111000 ' TMR0 clock source : RA4/T0CKI ' increment on low to high transition ' Prescaler assign to WDT ' WDT rate 1:1 ' INTCON = %10100000 ' Enable global interrupt ' Disable EE write interrupt ' Enable TMR0 overflow interrupt ' Variable definition ' ------------------- ' DisplayPort var PORTB ' Port for 7 Segments ;ClockInput var PORTA.4 ' Input pin for signal _7Seg1 con 14 ' enable more significant 7 segment display _7Seg2 con 13 ' enable mid significant 7 segment display _7Seg3 con 11 ' enable less significant 7 segment display Digit_1 var byte ' Hundreds digit Digit_2 var byte ' Tenth digit Digit_3 var byte ' Unit digit ToBeDisplay var word ' Result of count to be send to 7 segment display Display var byte ' Temp variable DisplayLoop var byte ' Delay var word ' Variable for Delay loop OverFlowVar var word ' Thousands var bit ' Flag for count >= 1000 & < 10 000 TenThousands var bit ' Flag for count >= 10 000 ;=========================================== Temp Var byte Temperature Var Word TempC Var Word I Var Byte Sign Var Word DQ VAR PORTA.4 DQ_DIR var TRISA.4 command var byte pis var byte ;============================================ ' Variable and software initialisation ' ------------------------------------ ' tobedisplay = 0 ' set initial value of count TMR0 = 0 ' reset prescaller On interrupt GoTo SetVarToBeDisplay Gosub init1820 ' Init the DS1820 command = $cc ' Issue Skip ROM command Gosub write1820 command = $44 ' Start temperature conversion Gosub write1820 Gosub init1820 ' Do another init command = $cc ' Issue Skip ROM command Gosub write1820 MainLoop: command = $be ' Read the temperature Gosub write1820 Gosub read1820 ' MainLoop ' --------- ' ' 1. display the result of the count on RA4 pin ' 2. refresh display ' 3. reset Timer0 ' 4. reload prescaler. ' ' Duration of the procedure : 1 sec ' fine tuned by DelayBetweenEachDisplay Sub ' ' Looping 1 sec and get results of the pulse count in ' TMR0 + OverFlowVar ' DisplayRefresh: ' ' Testing amount of count ' ----------------------- ' ' Get the result of count and place decimal point flag ' on the according 7 segments ' 'If tobedisplay>= 1000 Then 'tobedisplay = tobedisplay / 10 'Else ' tenthousands = 0 ' thousands = 1 'EndIf ' ' convert digit to 7 segment output pattern ' ----------------------------------------- display=ToBeDisplay dig 2 ' Read hundreds digit read display, digit_1 ' Convert hundreds if thousands==1 then digit_1=digit_1 & $7F ' enable decimal dot ' by clearing PORTB.7 display=ToBeDisplay dig 1 ' Read tenths digit read display, digit_2 ' Convert tens if tenthousands==1 then digit_2=digit_2 & $7F ' enable decimal dot ' ' by clearing PORTB.7 display=ToBeDisplay dig 0 ' Read units digit read display, digit_3 ' Convert units ' ' ' Send digit to 7 segments ' ------------------------ For displayloop = 0 To 111 ' loop for about 1 sec ' display hundreds ' ---------------- PORTA=_7seg1 ' enable hundreds 7 segment displayport = digit_1 ' display GoSub DelayBetweenEachDigit ' display tenth ' ------------- PORTA=_7seg2 ' enable tenth 7 segment displayport = digit_2 ' display GoSub DelayBetweenEachDigit ' display units ' ------------- PORTA=_7seg3 ' enable unit 7 segment displayport = digit_3 ' display GoSub DelayBetweenEachDigit Next ToBeDisplay = Temperature TMR0 = 0 ' reset prescaller GoTo DisplayRefresh DelayBetweenEachDigit: ' DelayBetweenEachDigit ' --------------------- ' Produce delay of about 3 mSec ' ' Fine tuned with MPLAB StopWatch to get MainLoop = 1 sec ' For delay = 1 To 307 @ nop Next @ nop @ nop @ nop @ nop @ nop @ nop @ nop Return disable SetVarToBeDisplay: ' ' SetVarToBeDisplay ' ----------------- ' interrupt routine of TMR0 overflow ' ' Reset prescaller ' Reset overflow flag ' Temperature = ((tempERATURE>> 1)*100)+((TEMPERATURE.0*5)*10) INTCON.2 = 0 ' clear overflow flag TMR0 = 0 ' reload TMR0 Resume enable '====================================================================================== ' Initialize DS1820 and check for presence init1820: Low DQ ' Set the data pin low to init Pauseus 500 ' Wait > 480us DQ_DIR = 1 ' Release data pin (set to input for high) Pauseus 100 ' Wait > 60us If DQ = 1 Then Pause 500 Goto mainLOOP ' Try again Endif Pauseus 400 ' Wait for end of presence pulse Return ' Write "command" byte to the DS1820 write1820: For pis = 1 To 8 ' 8 bits to a byte If command.0 = 0 Then Gosub write0 ' Write a 0 bit Else Gosub write1 ' Write a 1 bit Endif command = command >> 1 ' Shift to next bit Next pis Return ' Write a 0 bit to the DS1820 write0: Low DQ Pauseus 60 ' Low for > 60us for 0 DQ_DIR = 1 ' Release data pin (set to input for high) Return ' Write a 1 bit to the DS1820 write1: Low DQ ' Low for < 15us for 1 @ nop ' Delay 1us at 4MHz DQ_DIR = 1 ' Release data pin (set to input for high) Pauseus 60 ' Use up rest of time slot Return ' Read temperature from the DS1820 read1820: For pis = 1 To 16 ' 16 bits to a word temperature = temperature >> 1 ' Shift down bits Gosub readbit ' Get the bit to the top of temp Next pis If Temperature.15 then Temperature= ~Temperature +1 Sign = 1 Endif Return ' Read a bit from the DS1820 readbit: temperature.15 = 1 ' Preset read bit to 1 Low DQ ' Start the time slot @ nop ' Delay 1us at 4MHz DQ_DIR = 1 ' Release data pin (set to input for high) If DQ = 0 Then temperature.15 = 0 ' Set bit to 0 Endif Pauseus 60 ' Wait out rest of time slot Return ;================================================= END
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