Do you inadvertently have the watchdog timer enabled?

                                Regards,

                                  Jim



On Wed, 16 January 1980, sep wrote:

>
> Hello,
> [RE: "help me please!!" messages]
>
>
> To refresh memmory I am running the following code:
> -------------
> Main
>         MOVLW   h'06'           ; turn on an LED and a motor (h-bridge)
>         MOVWF   PORTB
>         NOP
>
> WaitHere
>         CALL    Delay2                  ; simply delay a little (it runs ok!)
>         BTFSC   PORTA,1         ; if pin 1 of porta goes high... turn everything off
>         GOTO    Finish
>         GOTO    WaitHere
>
> Finish
>         CLRF    PORTB                   ; NEVER PASSES THIS STAGE SINCE IT IS RESETING!
>
> dodod                                   ; loop doing nothing
>         NOP
>         CALL    Delay2
>         GOTO    dodod
>
>         END
> --------
>
> Well, what is happening is that the motor and an LED are turned and remain
> on as long as the pin 1 on porta remains low. That is all good. The
> problems happen when I turn the pin 1 on porta to high, the motor and the
> LED seem to stop. BUT then a reset happens to the chip and hence it
> oscillates, and never stopping.
>
> NOTE: motor is controlled by H-bridge (74F139)
>
> I don't want the chip to restart when the motor is turned on! I am propably
> doing something wrong!
>
> At the momment I have MCLR of the PIC through a 1K resistor to high, and an
> 0.1 capacitor to a low. The Vdd is connected to a high. Vss is connected to
> a low.
> Across my 5V regulator I have a 1000uF capacitor.
> Across the Vdd and Vss I have connected a 0.1uF cap.
>
> NOTE: the motors only require 2V, >30mA to run.
>
> I have checked all of the voltages on both the chips and they are both at
> 5V.
>
> Can someone help me in setting the circuit up such that PIC does not reset!
> I need to get this running by tonight, and I am having no luck.
>
> I will continue to test and if I get any progress I will let the list know,
> but so far I have been having no reset.
>
> I thank everyone for the help.
>
> -------------
> Sep. S.
> me@sep.2y.net
> -----------

jim@jpes.com