V ROM

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Revision as of 03:15, 12 April 2018 by Furrtek (talk | contribs) (TC5332204 info)
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File:V rom.jpg
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 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).