PIN C5 on the PIC18F2550- question?

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Hi

I have an LED attached to PIN_C5 on the PIC18F2550. When this LED is attached to PIN_C0 it flashes and works well. I now attach the LED to PIN_C5 and I get no signal out of C5 with the same code running (Except the code has been changed from PIN_C0 to PIN_C5).

Can someone please tell me what I am doing wrong?

Thank you
a.

[rnielsen]

Page 119 of the spec. sheet states:

[Ttelmah]

A classic 'read the data sheet' question....
Look at paragraph 10.3.
Read what it says half way down about RC4, and RC5 (normally used for the USB interface), and what they can do, when not used for this...

Best Wishes

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Hi

Thank you. I feel a bit embarased for not reading the data sheet.

Can you please tell me how to set the 3rd bit of UCON to 0? (UCON<3>=0) and the UCFG<3>=1?
i.e. how do I access the UCON and UCFG variables?

I appreciate all your help.
a.

[Ttelmah]

You need to look further.
Even when the USB is disabled, these two pins are _input only_.
The chip wakes up with USB disabled.
Te reason you are not getting output, is that the pins don't support it...
You can access any bit using the #bit directive.

Best Wishes

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Hi Ttelmah

Thank you for your explanation. Back to the drawing board for me.

All the best
a.

[rnielsen]

I just remembered that I ran into this exact same problem with this same part. I couldn't figure out why C5 would not output a signal until I dug into the spec. sheet and found it was only available as an input. It's buried in there good.

I used an 18F2525 in it's place. See if that one might be a good replacement for your application. It's a close pin-to-pin replacement.

Ronald

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Thank you all for your help!

Best Regards
a.