It seems to test individual 1-bit DRAMs in the video RAM check, so it only works for a SG-1000 and not the SG-1000 II which has two 4-bit DRAMs in pla...
It seems to test individual 1-bit DRAMs in the video RAM check, so it only works for a SG-1000 and not the SG-1000 II which has two 4-bit DRAMs in pla...