diff options
author | 2022-02-03 05:57:36 -0900 | |
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committer | 2022-02-03 09:57:36 -0500 | |
commit | 0bedd480184d34b7b90b17a1ac5e55b7277f9730 (patch) | |
tree | 8c11187a3b6f49b0317d5afdbf537c2a456cc757 /src/devices/sound/nes_defs.h | |
parent | 6c84aa716080b0eeea61bcad4388505b04d39370 (diff) |
nes_apu.cpp: Added noise channel period table for PAL systems. (#9256)
- Fixed a value in the parallel NTSC table for the largest period (lowest freq).
- Fixed a value in the counter length table (for all channels but DMC).
Diffstat (limited to 'src/devices/sound/nes_defs.h')
-rw-r--r-- | src/devices/sound/nes_defs.h | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/src/devices/sound/nes_defs.h b/src/devices/sound/nes_defs.h index bd0c3401a35..0a32a148de6 100644 --- a/src/devices/sound/nes_defs.h +++ b/src/devices/sound/nes_defs.h @@ -195,7 +195,7 @@ struct apu_t /* vblank length table used for squares, triangle, noise */ static const apu_t::uint8 vbl_length[32] = { - 5, 127, 10, 1, 19, 2, 40, 3, 80, 4, 30, 5, 7, 6, 13, 7, + 5, 127, 10, 1, 20, 2, 40, 3, 80, 4, 30, 5, 7, 6, 13, 7, 6, 8, 12, 9, 24, 10, 48, 11, 96, 12, 36, 13, 8, 14, 16, 15 }; @@ -205,10 +205,12 @@ static const int freq_limit[8] = 0x3FF, 0x555, 0x666, 0x71C, 0x787, 0x7C1, 0x7E0, 0x7F0, }; -/* table of noise frequencies */ -static const int noise_freq[16] = +// table of noise period +// each fundamental is determined as: freq = master / period / 93 +static const int noise_freq[2][16] = { - 4, 8, 16, 32, 64, 96, 128, 160, 202, 254, 380, 508, 762, 1016, 2034, 2046 + { 4, 8, 16, 32, 64, 96, 128, 160, 202, 254, 380, 508, 762, 1016, 2034, 4068 }, // NTSC + { 4, 8, 14, 30, 60, 88, 118, 148, 188, 236, 354, 472, 708, 944, 1890, 3778 } // PAL }; // dpcm (cpu) cycle period @@ -216,7 +218,7 @@ static const int noise_freq[16] = static const int dpcm_clocks[2][16] = { { 428, 380, 340, 320, 286, 254, 226, 214, 190, 160, 142, 128, 106, 85, 72, 54 }, // NTSC - { 398, 354, 316, 298, 276, 236, 210, 198, 176, 148, 132, 118, 98, 78, 66, 50 } // PAL + { 398, 354, 316, 298, 276, 236, 210, 198, 176, 148, 132, 118, 98, 78, 66, 50 } // PAL }; /* ratios of pos/neg pulse for square waves */ |