Under the Hood

The rest of this manual says what each part of Xpeccy+ does and where to find it. These pages say how some of it works, and why it was done that way: the details that are not obvious from the options, the problems behind them and how they were solved. Each page links to the settings it explains. The section grows as more is written.

  • Low input lag - where the delay between a key and the screen comes from, and how to get the least of it.

  • Anti-flicker - why Spectrum pictures flicker on a modern screen, and how the frames are mixed back without blurring what moves.

  • Tape loading by itself - how a loader is recognized, and what auto play, fast loading, flash loading and edge detection do with it.

  • Keeping time and going back - how the machine keeps its exact speed, what happens to the sound when time jumps, and how rewind keeps its history.

  • Contention, snow and the floating bus - the processor and the picture sharing memory, and the three effects that come out of it.

  • A folder as a disk - how a folder becomes a FAT32 disk, and how what the machine writes gets back into it.

  • What a quick save keeps - how the running game is found, where its saves go and what they carry.

  • SZX snapshots - what Xpeccy+ keeps in an .szx file, field by field, for the authors of other programs.