PIC16F887 PORTA problem

#1 · September 2, 2025, 11:58 am

Hi together,

I tried to use a PIC16F887 PORTA as output. I set all needed configurations (in my opinion), such as:

FOSC in CONFIG1 as INTOSCIO (RA6/RA7 for IO),

OSCCON = 0b01110101; // OSC settings
ADCON0bits.ADON = 0; // ADC off
ADCON1 = 0x00; // Vref internal
ANSEL = 0x00; // PORTA analog off
ANSELH = 0x00; // PORTB/E analog off
CM1CON0bits.C1ON = 0; // Comperator 1 off
CM2CON0bits.C2ON = 0; // Comperator 2 off

and at last TRISA = 0x00; // PortA for output

But if I set PORTA = 0xFF, only bits 0..5 are set.

Can help anyone to find my mistake? Thank you very much!

#2 · September 7, 2025, 2:07 pm

Hi, thanks for reporting.

I'm not at my computer now, so I'm very limited, but if you share your hex file I can try to find what is happening.

#3 · September 11, 2025, 9:11 am

Hello arachofo,

sorry for my late replay. I send you attached a zip file with the hex file, the C source and the sim file.

The example here is only toggling PORTA, but RA6 and RA7 doesn’t work.

Thank you very much!

Best regards

Uploaded files:

TestPortA.zip

#4 · September 15, 2025, 10:29 am

Thanks for the files, but seems that the hex file does not match the source code, PORTA is doing nothing.