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saa1099.md

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Philips SAA1099

this was used by the Game Blaster and SAM Coupé. it's pretty similar to the AY-3-8910, but has stereo sound, twice the channels and two envelopes, both of which are highly flexible. the envelopes work like this:

  • an instrument with envelope settings is placed on channel 2 or channel 5
  • an instrument that is used as an "envelope output" is placed on channel 3 or channel 6 (you may want to disable wave output on the output channel)

effects

  • 10xy: set channel mode.
    • x toggles noise.
    • y toggles square.
    • this effect affects either the first 3 or last 3 channels, depending on where it is placed.
  • 11xx: set noise frequency.
    • this effect affects either the first 3 or last 3 channels, depending on where it is placed.
  • 12xx: setup envelope. this is a bitmask.
    • bit 7 toggles the envelope.
    • bit 5 toggles whether to use a fixed frequency or lock to the frequency of channel 2 or 5.
    • bit 4 sets the envelope resolution.
    • bits 1 to 3 set the envelope shape:
      • 000: always off
      • 001: always on
      • 010: down
      • 011: down loop (saw)
      • 100: up down
      • 101: up down loop (triangle)
      • 110: up then off
      • 111: up loop (reverse saw)
    • bit 0 sets whether the right output will mirror the left one.
    • this effect affects either the first 3 or last 3 channels, depending on where it is placed.

info

this chip uses the SAA1099 instrument editor.

chip config

the following options are available in the Chip Manager window:

  • sets the rate at which the chip will run.