There is no known method to read out the ROM data from HD6301V1 or HD6301Y0, I think all of his chesscomputers are using those chips.

Maybe it's possible to see the physical bits after decapping the chip and looking under a microscope. I know it's April 1st, but I'm not kidding, many internal MCU maskroms have been optically extracted like that. It's a lot of work.