I am unable to set RA5, RA6, and RA7 as outputs on the 16F88. Although the datasheet doesn't make it perfectly clear, I assume that RA5 can only be an input. But what could be wrong with RA6 and RA7? I don't think it's the code or my wiring because I can successfully use all the other 13 I/Os as outputs. Is there some "trick" to using RA6 and RA7 as outputs in the 16F88?

Thanks.

 

Did you set the outputs for digital I/O via tha ANSEL reg to turn off the analogue inputs?
The RA5 is input only.
Max.

 

Did you set the outputs for digital I/O via tha ANSEL reg to turn off the analogue inputs?
The RA5 is input only.
Max.

I think so. My initialization section when trying to use RA6 is as follows.

TRISA = %10111111
OSCCON = $60
ANSEL = 0

 

Have a look at the config word, oscillator options, because they can stop those pins being normal I/O.

 

Have a look at the config word, oscillator options, because they can stop those pins being normal I/O.

Correct. I just stumbled on the answer.

#CONFIG
__config _CONFIG1, _FOSC_INTOSCIO & _WDT_ON & _LVP_OFF & _CP_OFF

#ENDCONFIG

Thanks to you and Max.

 

Also Tracecom it's good to read the datasheet chapter "I/O ports" and sub chapter "PORTA" as it gives specific details of each port pin, and how that pin can be configured.