www.seanriddle.com/4125901.bin is TI-57? I think we'll need a new MCU core for this one. It will be interesting to emulate, but I won't put it on my TODO just yet. Maybe other devs are interested too?
Sean, If it's not too much time, could you use your bit-reading tools and make a rom'dump' of the CD2708 MCU from that high res image on siliconporn?