Thanks everyone for your answers!
The type of equipment it's in might help us.
Also a Service manual for it may have the part listing and device type.
The equipment is a bench multimeter (Solartron 7060).
This is on the processor board.
Service manual... eh... if only I could find one (have been searching one for months)...
Its almost certainly a 8050 cpu of some sort.
Says 8050 on it and those did come in 40pin dip packages.
It also looks old enough.
Amm... I think that's a date code (SeanB has just confirmed it).
Mask ROM version of the 6800 family, easy to see from the Motorola logo, the mask version number, ZC probably a customer number, the 0002 the mask number so either the second version after the first 10k units did not work or they did a firmware upgrade on the system, and the P indicating a plastic package. Could also be the OTP Eprom version of the 6800 processor, which was often done for low volume customers who would order 1000 at a time.
The 8050 is a date code, week 50 of 1980, reinforced by the support TTL being dated 1979 to 1981.
IC6 and IC7 were probably there for ROM chips used during the development cycle, so the 6800 is a version with 2k of ROM on die, and probably 128 bytes of RAM as well.
Probably a MC6802 or 6808, depending on what is connected.
http://www.andysarcade.de/data/electronics/components/6802_6808.pdf
If no rom chips, it is a MC6801. Most likely candidate for sure if there is no ROM or RAM on the board, it has a whole 2k of ROM ( you can fly to the Moon on 2k) and 128 bits of RAM.
http://www.andysarcade.de/data/electronics/components/6801_6803.pdf
I think you are on to something here: a quick check and it seems the pinout matches the one on the MC6802/8.
IC7 is an SRAM and IC8 (not IC6, the number is not that readable in the picture) is an EPROM.
Now, there is also an IC6, but that's not visible in the picture and it is an MC68488 (from what I could gather, that's for the GPIB interface).
Many thanks again,
George