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mg_notes:iie_card:problem_software [2019/10/14 03:54]
M.G. [Bitsy Bye]
mg_notes:iie_card:problem_software [2019/10/14 03:59] (current)
M.G. [Software That Uses the Floating Bus]
Line 28: Line 28:
 ===== Software That Uses the Floating Bus ===== ===== Software That Uses the Floating Bus =====
  
-The Card does not have any areas of floating bus.  Unused locations on the I/O page tend to return the last key pressed.+The Card does not have any areas of floating bus, and neither the Gemini chip nor the card electronics implement the Apple II video circuitry at all.  Unused locations on the I/O page tend to return the last key pressed.
  
-Most emulators don't get this right, either.+Many emulators don't get this right, either
 + 
 +The end result is that cycle counting programs that use “vapor lock” to synchronize the video will fail
  
 ===== Software that uses Double Low-res Graphics ===== ===== Software that uses Double Low-res Graphics =====