how to save value in pic16f84a

[ibra]

JanH..

i used this method as you wrote, and like you for control stepper motor.
but it did not work.

i posted a thread " problem with stepper " and attached my code for this.

here is my code, you can see and say.

[mackrackit]

janH,
The link I gave in post #3 http://www.picbasic.co.uk/forum/showthread.php?t=5649 is a discussion on how to force the PIC to save on a power down.

ibra,
I gave you some sample code for your stepper motors.("problem with stepper ") Did it work? If not, what happened?

[ibra]

mackrackit..

the sample code you wrote did not work, the stepper just moves to left for ever.


i changed my last code ..

i put a delay after read and write instructions, and i changed the place of write instruction.
after these changes the stepper just do its job in the first stage ( when p = 13 and return back) ...then it start to go left and right randomly.

after all this i read the eeprom postion of P, it gives me a big value than 13 !!.

i think that there some mistakes in logical operators i used..but i dont know where ?

this is my new code..

any idea plz??

[mackrackit]

ibra,

The code I gave was trying to show where, when, and how to write to eeprom. It should not have changed the operation? At some point 13 should have shown up.

I do not have a stepper on the bench at the moment so this is untested on my part.

The idea is to have positive data written after every CW step (P=P+1)and negative data after every CCW step(P=P-P).

IF PORTB.6 = 0 AND P<=13 THEN ;go RIGHT

 GOSUB RIGHT

 ELSE

 IF PORTB.7 = 0 AND P>=1 THEN ;go LEFT

 GOSUB LEFT

This looks like the random problem. P<=13 -- P>=1 Stuck between these values. It would have to be greater than 13 or less than 1 to stop.

Or, make PORTB 6 or 7 high in hardware and tell the PIC what to do when they are high. (STOP)

I will try to test with a stepper in a day or so.