>
> Can anyone tell me the requirements for programming the C54 in circuit,
> what do you need to do with the MCLR pin. I can't find any data in the
> microchip data book. I take it that the C54 can be programmed serially
> as it can be programmed with the D. Tait type of programmer.

No, nope, and not a chance.

The C54 has parallel programming only, cannot be programmed byt the D. Tait
type circuit and has no provisions for in circuit programming.

Think about a C55X or C62X type chip. Same footprint but is much closer to
a C84 than a C5X in terms of these issues.

BAJ