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When I had no computer, I wanted one of those <USD$200 ZX81s so badly – just from seeing it magazines, & maybe pressing some of its keys at the electronics coun

by gojomo 5y ago

When I had no computer, I wanted one of those <USD$200 ZX81s so badly – just from seeing it magazines, & maybe pressing some of its keys at the electronics counter of someplace like maybe a Sears. IIRC the video output often cut out whenever a user program was running? I'm sure I would have enjoyed having one, but was fortunate enough my parents picked up an Apple ][+ instead. Still, warm feelings towards that unit, & its series, as something that made home computing thinkable.

opencl 5y ago
Drawing video took up a very large fraction of the CPU cycles on the ZX81 so there was a 'fast mode' and 'slow mode'. Fast mode cut out video output when programs were running, slow mode left it on and ran at something like 1/4 the speed.
jacquesm 5y ago
On the ZX80 it was done in such a way that just processing your keyboard input caused the video to blank.
- gojomo 5y ago
  That rings a bell!
  - jacquesm 5y ago
    The scary thing: this all seems like yesterday to me. For years I thought we were counting up to when we die, but now I realize we are actually counting down.