Hi and thanks for this subforum! The Tomy Tutor is that similar to the TI-99 home computers, not just hardware wise, but especially software wise. How similar? Let's find out. At least to my knowledge there are no internal documents, specs or source codes for the Tomy computers available. The only option we have would be starting from a ROM dump of the system software and disassemble that.   There is a nice disassembler from mizapf within TiImageTool, you right clic