After I repaired my old Roland D70 and gave it to my niece, I kinda missed my first synthesizer and bought a second hand one again. However, it had old firmware (1.14) and the backlight was not too good anymore (common problem as the backlights tend to go after 20 or something years). I had some more plans as I read on a forum somewhere about a CPU upgrade for the D70.
After some research, I found out the D70 runs on an Intel N80C196KB (MCS 96 CPU family) at 12 MHz. To verify this, I opened up the D70 to take a look.
I also had to remove the clamp that secures the IC in its socket to properly read the number.
Sure enough, it’s the 12 MHz version. Now things get interesting. The Intel CPU has models that run at 12, 16, 20, 25 and 50 MHz. I would seriously doubt anything quicker was available than 16 MHz around 1992 so to stay on the safe side, I have ordered a 16 MHz version to experiment and see if it will work properly with the 1.19 software version (latest released version).