Re: HP71 memory module question Message #6 Posted by J-F Garnier on 7 Mar 2006, 4:03 p.m., in response to message #5 by Christoph Giesselink
Hi Christoph and Eric,
On my Emu71, I definitively took the easiest way: implement the memory with big 32k or 64k chips, without trying the reproduce the low-level details. For instance, Emu71 uses a single 32kb "chip" for the main memory, instead of the 4x4kb modules- each 4kb module being in turn made of 4x1kb 1LG8 chips - of the real hardware.
In the same way, keyboard and display are not simulated at low level in Emu71, but only at intermediate level (memory buffers). On the other hand, I think that it's very important to simulate the I/O environment, namely the HPIL devices, which are integral parts of the system.
This is my way of thinking calculator emulator/simulator: the exact internals don't matter, as long as no realistic user program (i.e. program that a user can key in, this includes I/O access and of course machine code) can make the difference, so any previous written software can be run on the emulator/simulator.
My Emu41/Emu71 don't even try to reproduce the look of the HP41/HP71, but they run most known software or modules (not all, for instance service modules only partially run - but they are not what I consider as realistic program).
Kind regards to both.
J-F
Edited: 7 Mar 2006, 4:19 p.m.
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