On the Apple II there's an interesting way to add a little color to the bitmap, since the high bit select the palette used for the three-and-a-half pixels represented by the byte. Like this: 0: Black, green, purple, white 1: Black, blue, orange, white Now this leaves room for three whole pixe...

I tried to put a floppy disk into my IBM model number "8525-001" and it doesn't seem to be processing it. The light below the floppy drive blinks yellow every once in a while (such as when I turn the machine on). I've tried the dir a: command to test the drive and only got an error message... Any...

Why is it Colecovision AC adapter so big? I never had seen someting like this in any console of the era or even after it. What are the design choices made by the designers? Was it to turn the project cost effective? Back in the 80’s, with the technology then available, can the designers had taken...

I remember reading (at the time when it was current) in a hobbyist magazine about a ZX Spectrum modification to map RAM into ROM (not unusual), and implementing CP/M for it. The author ended the article with the sentence (approximately) "And now you can use CP/M (the cassette tape version) and it...

Did Microsoft basic (or any of the OEM versions) ever use Z80 only instructions? For the purposes of this question I'm ignoring the equivalent of BIOS I/O layers which OEMs would have provided.