Does it work if you put it in reset (hold in reset and release from=20
reset) from the IDE with a programmer/debugger attached?

Other things that comes to mind:
All VDD pins (including AVDD) connected to VDD.
All VSS pins (including AVSS) connected to VSS.
VCap present and of required type (ESR) and value?
JTAG disabled (so it doesn't accidentally enter JTAG operation).
Does oscillator stop when pulling MCLR low?
Pullup on MCLR.
Any power surges when going out of reset?

/Ruben

> > Perhaps you have a zapped MCLR pin. Have you tried with
> > another chip?
>=20
> Yes, three straight out of the tube and a couple of older ones
> from a different batch
>=20
> Interestingly, if /MCLR is grounded when power is applied
> the LCD doesn't initialise. Nor does it when you release the
> button for /MCLR to go to its usual high. Using the LATB,0
> markers to view progress, it seems code is not being executed
> at all. The oscillator (HS crystal) is going though. The power
> needs to be cycled with /MCLR high to get the s/w running
> as you'd normally expect it to.
>=20
> So the button is doing "something". I must be missing a h/w
> directive somewhere but the path between pin and internal
> reset signal is pretty straight-forward
>=20
> Joe
>=20

--=20
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