I can't seem to find any information about the K053260 chip anywhere.
From what I know, it's a sample-based sound chip used by Konami that goes along the YM2151 sound chip in Asterix, Sunset Riders, Turtles in Time, and other arcade games from the same time period.
I'd like to know how many channels this contains and what quality samples it supports.
Anyone know where I can find this out?
Tech Specs of the K053260 Sound Chip?
- Jedi QuestMaster
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Re: Tech Specs of the K053260 Sound Chip?
MAME's source has an implementation. Looks like four 8-bit DACs with some kind of compressed format feeding it.
Re: Tech Specs of the K053260 Sound Chip?
A lot of arcade machines use an OKI chip for digital samples, which uses a 4-bit (I think) adpcm format; same as the .vox format. Without looking at the implementation, this could be the compression scheme.
- Jedi QuestMaster
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Re: Tech Specs of the K053260 Sound Chip?
Thanks.
Those MAME pages came up, but I didn't know what I was looking at.
Those MAME pages came up, but I didn't know what I was looking at.
Re: Tech Specs of the K053260 Sound Chip?
Jedi QuestMaster wrote:Those MAME pages came up, but I didn't know what I was looking at.
→ 4 channelshttp://mamedev.org/source/src/emu/sound/k053260.c.html wrote:Code: Select all
39 k053260_channel channels[4];
→ 8 bit DACCode: Select all
169 if ( ppcm_data[i] > 127 ) 170 ppcm_data[i] = 127; 171 else 172 if ( ppcm_data[i] < -128 ) 173 ppcm_data[i] = -128;
→ 7 bit volume control and 3 bits panning per channelCode: Select all
361 case 7: /* volume is 7 bits. Convert to 8 bits now. */ [...] 378 case 0x2c: /* pan */ 379 ic->channels[0].pan = v & 7; 380 ic->channels[1].pan = ( v >> 3 ) & 7;
Various things I find odd:
1-the packed PCM (a more advanced DPCM than the NES uses, closer to conventional ADPCM) is signed but the raw PCM is unsigned. The IC probably converts the unsigned data to signed before volume and panning.
2-the panning code doesn't provide the ability to pan things hard left. It seems more likely to me that the IC doesn't provide the ability to pan things dead center