Problems using 18F4585

[barrylorimer]

Hopefully someone can help me here.

I've written a very simple flowchart which is as basic as switching a few output ports on and off for the purpose of a small test program we need (RB4, RB5, RC2, RD4). Now, this program works a treat on the PIC16F877a but when I switch the chip in flowcode to an 18F4585 everything seems to compile an program fine but the pic does nothing on reset/switch on.

I am programming the pic via another means so using flowcode to write a hex file, so there are no issues with USB programming or anything like that. And, I have gone through all the usual setup checks (PortB is set to digital output) and compared the datasheet with the expert configuration setup for the chip but with no success.

Can anyone think of something I might be missing?

Many thanks, Barry.

[Benj]

Hello Barry

Sounds like a configuration problem, what is your configuration eg crystal speed, MCLR setting etc

If you are using the standard 19.6608 MHz crystal and are providing 5V to the MCLR pin then the following settings should work for you.

[barrylorimer]

Hi there Benj,

Many thanks, that's got it working. I went through all the differences between our configurations one by one and it turns out the problem was the oscillator setting. I was under the impression that using XT or HS would make little difference in my project but I realise my mistake now having had a closer look at the datasheet.

Thanks again!!!