Repair help

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Revision as of 05:12, 30 June 2011 by SMKDAN (talk | contribs) (MVS)
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MVS

No sound

  • Backup RAM corrupt, SOUND_STOP ($D00046) is non-zero. Clear Backup RAM.

Z80 error

Can be caused by bad components / continuity with the following:

  • Z80 <-> SM1
  • Z80 <-> RAM

Second generation specific (todo: get pin numbers in a nice table)

  • Z80 <-> NEO-D0 (NMI,A2-A4,IORQ)
  • Z80 <-> NEO-C1 (Z80 D0-D7)
  • NEO-D0 <-> NEO-C1 (Z80R,Z80W,Z80CLR,SDW)