fruit-bat / pico-zxspectrum

ZX Spectrum for Raspberry Pico Pi RP2040
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Are these implementations cycle-accurate? #113

Closed Ev1lT3rm1nal closed 9 months ago

Ev1lT3rm1nal commented 10 months ago

AFAIK this replicates exactly the process made by a real spectrum, and I'd like to know if it is cycle-accurate

fruit-bat commented 10 months ago

Short answer is no... but in places it's not bad. It can read audio signals real time. The USB is handled on the same core as the emulator which causes glitches that are subsequently corrected for. The ay audio is split in half so some of it runs with the cpu but the rest is clocked at a constant rate so pitch does not alter with cpu speed. And so on.