16F913 RA7 Pin control problem

[Wayne]

Hi Mr. E

I have setup the program in the MPLAB Sim and this is what happens.
I set the config bits to use INTOSCIO in MPLAB.
then compile and run in the sim.
TRISA.6 and TRISA.7 read as "1"
after TRISA.7 = 0
LOW PORTA.7 the port reads "0" but it is in tristate ( on the PCB)
there is a 20K res to vcc going to RA7 always high.
when I write a "0" to PORTA.7
It looks like the 16F913 thinks it is in one of the external modes.
But with no xtal on the PCB how could it run.
All other functions of the program work.
I changed the program to use RB6 and it works, but I need RB6 for other things.


The line below is from the data sheet.
Note: TRISA<7:6> always reads ‘1’ in XT, HS and LP OSC modes.
But it is in INTOSCIO mode

Thanks
Wayne

[modifyit]

Wayne,

Did you happen to find the solution to this issue? I am trying to do the same thing on a 16F690 and porta.4 is not controllable. It just sits there oscillating up and down when I try to set it as an output.

I can control any other pin on portA, just not RA4.