Richard,


Did you turn off the analog comparators?
If not, do that with CMCON =3D 7;

If the comparators are not disabled, RA0 through RA3 become analog and
they are read always as '0'.
That would create RMW problem if you change each bit individually,
because this PIC doesn't have LAT register.


Cheers,

Isaac


Em 20/10/2015 09:36, Richard R. Pope escreveu:
> Issac,
>      The problem is going to be in the configuration of the 16f877a.=20
> There is no activity on the en or the r/s pins. Argh! I thought that=20
> this might be the problem. The clock is running. I have every reason to=20
> believe that the pins are not set for digital I/O. Here is the setup=20
> statements:
>          TRISD =3D 0;
>          TRISA =3D 0;
>          ADCON0 =3D 0;
>          ADCON1 =3D 0;
>          CMCON =3D 0;
> Any more thoughts on this?
> Thanks,
> rich!
>
> On 10/20/2015 6:04 AM, Isaac Marino Bavaresco wrote:
>> Richard,
>>
>>
>> You could create an infinite loop sending just one and the same command
>> to the LCD, then your scope would synch with, say, the ENABLE signal and
>> keep the image steady.
>>
>>
>> Isaac
>>
>>
>> Em 20/10/2015 07:31, Richard R. Pope escreveu:



--=20
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