Texas TI-66 Programmable: Toshiba skills to rescue Texas...

[brouhaha]

(12-18-2017 09:14 AM)HrastProgrammer Wrote:  It would be great if the ROM could be dumped from this calculator ...

...and if we knew anything about the processor architecture. Maybe it matches one of the TI CMOS calculator processor architectures, and maybe not.

The package appears to match the TMP47C22F of the Toshiba TLCS47C family of 4-bit microcontrollers, but the pinout does not. The LCD drive of the part is comparable to the TI-66 requirements. It has 2Kx8 ROM and 192x4 bits of RAM. Doesn't seem like enough ROM. There were later versions with 4Kx8 ROM and 256x4 RAM, but the match the pinout of the C22F, and not that of the T6875A.

If it's a Toshiba architecture, it probably matches the TLCS47C.