Correct envelope period for internal double-resolution.

TomHarte / CLK

A latency-hating emulator of: the Acorn Electron and Archimedes, Amstrad CPC, Apple II/II+/IIe and early Macintosh, Atari 2600 and ST, ColecoVision, Enterprise 64/128, Commodore Vic-20 and Amiga, MSX 1/2, Oric 1/Atmos, early PC compatibles, Sega Master System, Sinclair ZX80/81 and ZX Spectrum.

MIT License

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Correct envelope period for internal double-resolution. #1341

Closed TomHarte closed 7 months ago

TomHarte commented 7 months ago

Précis/reminder-to-self:

the AY does its envelopes with 16 levels of volume precision;
the YM doubles that to 32 levels;
my implementation use a half-a-real-AY internal clock divider so that it can generate the YM-style envelopes if asked;
it doubles the programmer-supplied tone and noise periods to make up the difference.

... but, here's the bug: it wasn't doubling the envelope period.

Fixed.

Affects #1339 and possibly resolves it. More testing to do.