4 ms·
Reading back over my comment I could have used some of that :) But yes, I was focused on just pulling down and displaying a comment, not even touching on the i
by jameshart 5y ago
Reading back over my comment I could have used some of that :)
But yes, I was focused on just pulling down and displaying a comment, not even touching on the input processing capabilities.
And this is stuff that a computer does without even breaking a sweat - this is just constant background activity supporting the vastly more complex stuff the machine can do if you task it to.
A ZX Spectrum reading data from a tape drive at about 1400 bits per second required almost its entire CPU’s attention. At that speed just loading the 1614 UTF8 bytes of my comment above into memory would take over 9 seconds, during which time the computer is doing literally nothing else.
- gus_massa 5y agoI had a ZX81 with the extra package of 16 KB of RAM (not a typo, only KB). During load and save time, the screen was just noise because the CPU handle the TV signal and it can't load the data and keep updating the screen.
- jameshart 5y agoThe ZX80 could literally not do screen sync when the CPU was doing anything else at all. Pressing a key would cause the screen to go flicker.
- sys_64738 5y agoThere were some ingenious games for the ZX80 which used cycle counting to precisely time the beam being offscreen to process keyboard input. This allow flicker free keyboard games like you can see on YouTube.