Difference between revisions of "V ROM"

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(TC5332204 info)
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[[File:v_rom.jpg|thumb|right|4MiB V ROM]]
 
[[File:v_rom.jpg|thumb|right|4MiB V ROM]]
"'''V'''oice" ? 8-bit ROMs containing [[YM2610|PCM]] audio samples in [[cartridges]].
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The '''V'''(oice ?) ROMs contain the [[ADPCM]] audio samples in [[cartridges]].
  
In early games, the ADPCM-A and ADPCM-B samples were split in separate V ROMs. Later, the {{Chipname|PCM}} chip was made to allow both types of data to be mixed in the same ROM(s).
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In early games, the ADPCM-A and ADPCM-B data was stored in separate V ROMs. Later, the {{Chipname|PCM}} demultiplexer chip was made to allow both types of data to be mixed in the same ROM(s).
  
V A ROMs minimum speed: any will do (>2µs).
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The TC5332204 mask ROMs have a similar pinout to the 27C322 EPROMs. The only difference is that they're set to byte mode only: the /BYTE pin is used as A20, and half of the data output pins are unused.
  
V B ROMs minimum speed: 250ns (see [[YM2610 bus timing]]).
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==Speed==
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* V A ROMs minimum speed: any will do (>2µs).
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* V B ROMs minimum speed: 250ns (see [[YM2610 bus timing]]).
  
 
[[Category:Chips]]
 
[[Category:Chips]]
 
[[Category:Cartridge systems]]
 
[[Category:Cartridge systems]]

Revision as of 05:15, 12 April 2018

4MiB V ROM

The V(oice ?) ROMs contain the ADPCM audio samples in cartridges.

In early games, the ADPCM-A and ADPCM-B data was stored in separate V ROMs. Later, the Chipicon.png PCM demultiplexer chip was made to allow both types of data to be mixed in the same ROM(s).

The TC5332204 mask ROMs have a similar pinout to the 27C322 EPROMs. The only difference is that they're set to byte mode only: the /BYTE pin is used as A20, and half of the data output pins are unused.

Speed

  • V A ROMs minimum speed: any will do (>2µs).
  • V B ROMs minimum speed: 250ns (see YM2610 bus timing).