The TMS1000C is documented in the same pdf as TMS1400. It mentions that it has a 3-level stack and has an external HALT pin, but is otherwise same as PMOS TMS1000 from software point of view. Could you decap this one? (I mean, whether or not you're able to dump it electronically)
I wasn't able to figure out how to dump it electronically, but the decap went well: http://www.seanriddle.com/tms1000.html#xl25 It looks like they expanded the O Output PLA to the full 32 entries. I don't know if the ROM array is in the same physical order as on the PMOS chip.
