Re: are there any real voyager emulators Message #2 Posted by Nelson M. Sicuro (Brazil) on 9 Dec 2003, 8:27 p.m., in response to message #1 by hugh steers
The voyagers' processors are NUT CPUs very much the same as of the HP-41. The only differences are:
1) Clock (~230KHz)
2) Voltage (3~5V)
3) It doesn't use the signal of "power good", the display chip handles the low battery test (I doesn't remember now the name)
The opcodes are exactly the same. I'm managing to get the ROM of my 12C/15C dumped, isn't that hard (I only need to build a logic analyzer with my PC's parallel port).
The signals are the same, ISA, SYNC, DATA, Clock1&2. The earlier ones have the RAM/LCD+ROM chips external, and the signals are accesible. I played with a scope, they are all there... I even "watch" the ROM dump in the self-test!
I think that *will be* emulators for them, I'm myself trying do to it. I also think that most people found that it will be very difficult to get the ROM dumped, or only tried on the new ones (only one chip).
Best regards
Nelson
Edited: 9 Dec 2003, 9:20 p.m.
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