Date   : Mon, 12 Sep 1994 11:25:33 +0000
From   : lamcw <lamcw@...>
Subject: port &FE60 output

hi everyone,

thanks to all for your help about &FE60. in snapper there's the code

loop:
  LDA &FE60
  CMP &FE60
  BEQ loop

now either the output must change (which it can't do unless something is
attached to the user port OR programmed in some weird way) OR it shouldn't
reach this bit of code. i've got snapper to work by poking random values into
this location but it's hit and miss. also the game seems very fast as Alan
Hart mentioned from his experiences. maybe a value of &FF will bypass
the above code. does the original snapper run on a Master?

that's the problem with implementing bits and pieces of this chip and that,
the side effects of leaving parts out are difficult to track. chances are
snapper "thinks" there's something attached to the user port when in fact
there isn't.


chris lam.