syntax error

[Darrel Taylor]

I think this should do it.
Set ADchan before GOSUBing ...

Result       VAR WORD

GetSetpoint:
    GOSUB GetADC
    Result  = ADvalue*(MaxSetPoint - MinSetPoint)
    Result  = (DIV32 ADmax) + MinSetPoint
    Setpoints(ADchan) = Result
RETURN

hth,

[malc-c]

Darrel, I've tried you code, may not of put it in the right place

Main:
    FOR pid_Channel = 0 TO 3              ; cycle thru all sensors
        GOSUB SelectSensor
        GIE = 0                           ; disable interrupts before 1-wire
        @  DS1820_Convert                 ;   start a temperature conversion
        GIE = 1                           ; enable interrupts after 1-wire
    NEXT pid_Channel
    
Result       VAR WORD

GetSetpoint:
    FOR ADchan = 0 to 3
    GOSUB GetADC
    Result  = ADvalue*(MaxSetPoint - MinSetPoint)
    Result  = (DIV32 ADmax) + MinSetPoint
    Setpoints(ADchan) = Result 
    LCDOUT $FE,$C0, dec setpoints(0)>>1,"   " 
    NEXT ADchan

but the set point displayed in hyper terminal is still twice the value shown on the lcd.

[Darrel Taylor]

LCDOUT $FE,$C0, DEC setpoints(0)/10,".",DEC1 setpoints(0)//10

[malc-c]

LCDOUT $FE,$C0, DEC setpoints(0)/10,".",DEC1 setpoints(0)//10

Thanks.

I tried changing the results value (dividing by 2 and then multiplying by 2) to no avail.

How does dividing by 10 work out then ? If the result value was giving me a setpoints value of 100, but it was displaying 20.0 on the screen, dividing 100/10 gives 10 which would equate to 1.0 degree ??

Just can't get my head round this... maybe I've been at it too long... or had too many glasses of wine !

[Darrel Taylor]

value = 100
value / 10 = 10
value // 10 = 0

DEC value /10,".",DEC1 value//10 = "10.0"<hr>
value = 342
value / 10 = 34
value // 10 = 2

DEC value /10,".",DEC1 value//10 = "34.2"
<br>

[malc-c]

Cheers DT !

[malc-c]

Guys,

Is A/D handled different in an 18F4550 to a 16F877A ?

The development of the 4ch PID thermostat with Darrel got as far as porting the original code to a 18F4550 (mainly as it has a lot more code space). I've copied over the A/D from the 16F code

;----[Analog Settings]------------------------------------------------------
DEFINE ADC_BITS 10                ' Set-up ADC for fastest 10-bit results
DEFINE ADC_CLOCK 2
DEFINE ADC_SAMPLEUS 5
INCLUDE "DT_Analog.pbp"

MaxSetPoint  CON 350              ' Pot fully clockwise
MinSetPoint  CON 100              ' Pot fully counter clockwise 
ADbits = 14                       ' set A/D resolution to 14-bits
CMCON = 7                         ' disable Comparators
ADCON1 = %10000010                ' AN0-4 Analog, Right justify
ADCON1 = $0F

And have the same routine for using the value to set the set point

GetSetpoint:
    FOR ADchan = 0 to 3
    GOSUB GetADC
    Result  = ADvalue*(MaxSetPoint - MinSetPoint)
   Result  = (DIV32 ADmax) + MinSetPoint
    Setpoints(ADchan) = Result 
    NEXT ADchan

But when viewed on the PC via Hyperterminal the set point is either 10 or 110.

I've tried changing the two values for minsetpoint and maxsetpoint to no avail.