Thermo 7 segments - little problem

[fratello]

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 .

' 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

[Demon]

What if you comment the DS1820 logic, set temperature and sign to -20 and test only the display logic?

Robert

[AvionicsMaster1]

Near the top of the program you set up a config line but it's commented out. I think for that chip to need to set the HS osc since you're using a 20Meg unit.

Do you also need to set the CONFIG register to set for oscillator speed and type?

I'm looking over the data sheet but have to catch it in fits and starts. More questions later.

[fratello]

Thanks for advice ....
Indeed I commented this : ";@ __config _HS_OSC & _WDT_ON & _PWRTE_ON & _LVP_OFF"
But in Proteus I set the freq to 20 MHz.
If I write "temperature=123", the display show "12.3" ; so, it's work ...but the reading of sensor not work / or the temperature is wrong calculated ...

[Demon]

So the LCD logic works, that's a start.

Are you doing this only in proteus?

Robert

[fratello]

No, I have builded the hardware too ...
Note : the code for temperature sensor is for DS1820 ; I use DS18B20 - maybe this is the problem ?!

[Archangel]

Hello Fratello,
your code

PORTA=_7seg1        ' enable hundreds 7 segment
        displayport = digit_1 ' display
        GoSub DelayBetweenEachDigit

Best I remember and for reasons I don't you cannot assign a port value just that way. Something about BLA = bla being a T/F comparason rather than assignment, don't remember just fuzzy . . . I believe PORTA=_7seg1 is a comparason operator and putting ! or ~ ahead of it converts it to a "Bitwise" operation
Try this

PORTA=~_7seg1        ' enable hundreds 7 segment
        displayport = digit_1 ' display
        GoSub DelayBetweenEachDigit
and if that inverts your display then use 2 nots
PORTA=~~_7seg1        ' enable hundreds 7 segment
        displayport = digit_1 ' display
        GoSub DelayBetweenEachDigit

As I have not really studied your code I may have misread where your port display is, in any event use not or 2 nots before that port assignment.

[AvionicsMaster1]

A couple of other things I question:Please bear in mind I'm not a real programmer just a poor hacker!

You say you set a rate in Protues but don't you have to have those configs to set the chip up to work at that speed even in Proteus?

Once you go through the mainloop you never go back to it. I don't see a line in your code where you have goto mainloop anywhere.

On the write1820 sub, and some others, you write either a 0 or a1 then shift if right 1 digit. Won't that constantly shift in a zero? And in same sub there are 8 bits to a byte but I think they shouldstart at 0 not 1. I don't really understand how that works so if I'm wrong I'll look up the 1820 and get schooled up.

[AvionicsMaster1]

A couple of other things I question:Please bear in mind I'm not a real programmer just a poor hacker!

You say you set a rate in Protues but don't you have to have those configs to set the chip up to work at that speed even in Proteus?

Once you go through the mainloop you never go back to it. I don't see a line in your code where you have goto mainloop anywhere.

On the write1820 sub, and some others, you write either a 0 or a1 then shift if right 1 digit. Won't that constantly shift in a zero? And in same sub there are 8 bits to a byte but I think they shouldstart at 0 not 1. I don't really understand how that works so if I'm wrong I'll look up the 1820 and get schooled up.

[fratello]

Thank you all for support !
1. The code (last version, from previous page) work fine - at least show a clear, flicker-free suite of "0" , if I comment all references to temperature ...
The "copyright code" belong to Mr.Monfette (' File name : Count_Display.bas ' Company : Mister E ' Programmer : Steve Monfette) so it's a WORKING code for LED display. Me, I just attempted to adapt to my project - reading DS18B20 sensor !
2.If I write in code this line "temperature=123" (instead "calculated" value of temperature), the display show "12.3" ; so, it's work ...but the reading of sensor not work / or the temperature is wrong calculated ...
3.Indeed, the return in loop was to "DisplayRefresh:", not to "Mainloop:". I've changed that, but not results !
...