🚀 go-pugleaf

I have a few somewhat unrelated questions.
1) I have a dowty Quattro modem. It contains the PIC7001 microcontroller,
which is described as TMS7000 series pin-compatable, romless by microchip
corp. If I replace it with a TMS77C82, the modem no longer works. But it
fails in a a way which suggests that the chips are similar - the right
patern of lights appears on the front, but it ignores the switches. It
also seems to ignore the serial port, but checking with a logic probe on
the microcontroller pins makes me think that TxD has somehow moved to
another pin. 
  BTW, the chip is strapped to disable internal ROM, and there is a 32K
rom, 8K ram on the modem PCB. Is there any way I can use a TMS77C82 here
(the PIC7001 is no longer made, and I would like to have a back up if it
ever failed)

2) Greenweld ( a surplus dealer in England) are selling 'Zonphone
terminals' at the moment. They were part of a portable 'phone system, and
contain 4 microporcessors, several gate arrays, etc. I am hacking about
inside one, and wonder if anyone can identify either of the following
chips?
  TMS77C01 (seems to be linked to a couple of TMS77C82 microcontrollers,
but is not a processor itself )
  CLA5531 (Plessey - may be another gate array - anyone know for sure)

-tony 'PDP11 Hacker' Duell
ard@siva.bris.ac.uk