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Hi, i'm using the COUNT command along with an asm interrupt wich shows in a display de variable used by count.
without the interrupt the commad works fine, but now I'm getting all kind numbers.
Is there any special variable used by count that I need to save before the interrupt for it to work ok?
IMO, disable interrupt before counting will solve the problem, but there's certainely other way ...See section 9.3 of the PBP manual. It must point you in the right direction.
BTW wich PIC are you using ? you can look in the according PBPPICXXX.LIB to see what value are use in COUNT. Try R1 and W.
regards
It's always a good idea to post your code. It's difficult to help otherwise ........
Count uses FSR and RM1. FSR needs to be saved and restored in your ASM blocks. RM1 is a PBP variable and needs to be saved and restored the same way as R0,1,2 and 3.
It's always a good idea to tell wich PIC and compiler you're using.Code:
fsave var byte bank0 system
rm1 var word bank0
asm
display
movwf wsave ; display rutine
swapf STATUS, W
clrf STATUS
movwf ssave
movf PCLATH, W
movwf psave
movf FSR,w
movwf fsave
endasm
r0save = R0
r1save = R1
r2save = R2
r3save = R3
rm1save = RM1
'blah blah ......
R0 = r0save
R1 = r1save
R2 = r2save
R3 = r3save
RM1 = rm1save
asm
bcf INTCON, 1
movf fsave,w
movwf FSR
movf psave, W
movwf PCLATH
swapf ssave, W
movwf STATUS
swapf wsave, F
swapf wsave, W
retfie
endasm
/Ingvar
Hi, here is the code I i'm using to test count and asm interruprs with a 16f84a, some var are in sapanish, I hope it's no a problem to understand it, I can't find what is wrong with it.
define osc 20
clear
pulsos var byte
x var word ; display value
num var byte
velocidad var byte
wsave var byte $20 system
ssave var byte bank0 system
psave var byte bank0 system
r0save VAR WORD bank0
r1save VAR WORD bank0
r2save VAR WORD bank0
r3save VAR WORD bank0
fsave var byte bank0 system
rm1save var word bank0
TRISA = %11111111
TRISB = %00000000
goto start
define INTHAND display
start:
option_reg = %00000011
intcon = %10100000
main:
count porta.2,1000,pulsos
x = pulsos
goto main
asm
display
ENDASM
r0save = R0
r1save = R1
r2save = R2
r3save = R3
fsave = fsr
rm1save = RM1
ASM
movwf wsave
swapf STATUS, W
clrf STATUS
movwf ssave
movf PCLATH, W
movwf psave
endasm
num = x dig 0
portb = num
high portb.4
pause 7
low portb.4
num = x dig 1
portb = num
high portb.5
pause 7
low portb.5
num = x dig 2
portb = num
high portb.6
pause 7
low portb.6
TMR0 = 60
INTCON.2 = 0
asm
movf psave, W
movf psave, W
movwf PCLATH
swapf ssave, W
movwf STATUS
swapf wsave, F
swapf wsave, W
endasm
fsr = fsave
R0 = r0save
R1 = r1save
R2 = r2save
R3 = r3save
RM1 = rm1save
asm
retfie
endasm
Hi,
First of all ...... you didn't follow my instructions, the saving and restoring of PBPvariables and registers are shuffled. Not that it matters much, it will not work anyway. Now when i see your code, i understand what you're trying to do. It will not work for several reasons .... the most obvious one beeing that your interruptroutine will take much longer time than the timer needs to rollover. This means that your pic will be busy handling the display almost all the time. That leaves virtually no time to count pulses. It can be done if you write a true assemblerinterrupt and slow the display. I would have helped you but i'm going away for the hollidays. Perhaps someone else could help, there must be somone more than me that have done this in the past.
/Ingvar
Hi, I did follow your instructions and everithing is working fine now, thanks a lot.
Some how I post and older code, I didn't notice, sorry.
And thanks again because I'm new with pics and this help me a lot.