Apple-2-SW/prog8
1
0
Fork 0
mirror of https://github.com/irmen/prog8.git synced 2024-11-22 15:33:02 +00:00
Code Issues Projects Releases Wiki Activity

psg comment

Browse Source
This commit is contained in:
Irmen de Jong 2023-04-24 01:23:03 +02:00
parent 50604c25c2
commit cd8e7f3912
2 changed files with 7 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
compiler/res/prog8lib/cx16/psg.p8
View File

@ -75,8 +75,11 @@ psg {
; -- Enables AttackSustainRelease volume envelope for a voice.
; Note: this requires setting up envelopes_irq() as well, read its description.
; voice_num = 0-15 maxvolume = 0-63
; attack, sustain, release = 0-255 that determine the speed of the A/D/R.
; TODO describe how the speeds are calculated. For now, experiment. Higher values means *slower* enveloping.
; attack, sustain, release = 0-255 that determine the speed of the A/D/R:
; attack time: MAXVOL/15/attack seconds. higher value = faster attack.
; sustain time: sustain/60 seconds higher sustain value = longer sustain (!).
; release time: MAXVOL/15/release seconds. higher vaule = faster release.
envelope_states[voice_num] = 255
envelope_attacks[voice_num] = attack
envelope_sustains[voice_num] = sustain

2
docs/source/libraries.rst
View File

@ -383,3 +383,5 @@ Available for the Cx16 target.
Contains a simple abstraction for the Vera's PSG (programmable sound generator) to play simple waveforms.
It includes an interrupt routine to handle simple Attack/Release envelopes as well.
See the examples/cx16/bdmusic.p8 program for ideas how to use it.
Read the source of this library module for details about the API.