This article is from the Apple II Csa2 FAQ, by Jeff Hurlburt with numerous contributions by others.
$00 Unknown, probably means that the RamFAST is very confused
$01-08 DRAM memory test failure
$09 EPROM checksum failure
$0C Z180 processor crashed, indicates some hardware fault
$0D Error writing cache data to disk
$0E Termination power error
 
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