piclist4@xargs.com wrote:
>> No, the dedicated programming port is always "live" for programming
>> when you raise the Vpp line of the dedicated port,
>
> If that's true, it doesn't work with the REAL ICE.  The REAL ICE reads
> zeros for the device ID when trying to enter programming mode on the
> dedicated port with ICPRT =3D 0.

Like I said, I've got virgin chips that have only ever been programmed over
the dedicated programming port.  This works for debugging with a RealIce
too.  It may very well be that ICPRT =3D 0 disables that.  The disconnect m=
ay
be that chips are shipped from the factory with the dedicated programming
port enabled.  That may not be what the documentation says, but it makes
sense when you think about it.

>> if you've enabled the port by tying a line high.
>
> If you're referring to the ICPORTS pin, that enables 28-pin emulation
> when low.

Yeah, you're right.  I had just taken a quick look at a schematic using a
18F4550 and saw that line tied high and misremembered that it had something
to do with enabling the port.


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