furnace/papers/doc/7-systems/zxbeep.md
freq-mod 4d7c1c9e44
docs update (#519)
* docs update

mentions of fractal, new chips documentation, and other minor stuff

* add a link to the Fractal repo

as suggested by @breakthetargets

* better wording, less typos
2022-06-06 16:49:39 +02:00

558 B

ZX Spectrum Speaker

Rather than having a dedicated sound synthesizer, early ZX Spectrum models had one piezo beeper, controlled by Z80 CPU and ULA chip. It's capabilities should be on par with an IBM PC speaker... right?

Not really - very soon talented programmers found out ways to output much more than one square wave channel. A lot of ZX beeper routines do exist, as of 0.6pre1 Furnace supports only one - Follin-like engine with 6 channels of narrow pulse wave and click drums.

effects

  • 12xx: set pulse width
  • 17xx: trigger overlay drums.