Hello-
I bought a 2nd I/O ROM recently for a second HP-85 that I have, but it doesn't seem to work. For example, it reports "syntax error" when I type output and return.
On the I/O ROM that does work, I get "invalid parameter" when I type just output and return (because I haven't given it a parameter). This is okay and expected.
My questions are:
1. The ROM that works is not marked with any "revision" information. The one that does NOT work is marked "revA".
Is there some difference in syntax for the output command that I'm unaware of?
2. If, by chance, this I/O ROM is bad, is there a way that I can replace it with a copy of a good one? (EPROM?) Has anyone disassembled one of the modules to look?
-Mike