>
> > I've connected up a PIC 16C74 on a breadboard, and am feeding in a
> > 4Mhz signal onto pin 13 (the Clk in pin) from a signal generator.
> >
> > I'm applying 5v to pins 11 & 32, with 0v on 12 & 31
>
> What about /MCLR?  If you don't pull it up, the chip will stay in reset.
> What oscillator mode are you using?

I've tried with it pulled up, seems no go still :(

The oscillator is in XT mode, the signal is coming from a function generator

>
> > So I wrote a small program (very small :) to turn port D into an output
> > and blat bits out of it, incrementing. .  such as this
>
> You're using the outputs "open-collector"?  It looks like you're writing to
> the TRIS registers? [bcf RP0 to avoid that methinks]
>

What will a bcf RP0 do then?

Thanks,

Glyn

--

Glyn D / http://www.cs.man.ac.uk/~daviess / Computer Science 3rd year

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              "Whom computers must destroy, they must first drive mad."
                                                        -- fortune

                                     "What if everyone felt like that?"
                                                        -- Catch 22
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