GoKawiilA Mitra-15 Simulator for SIMH
This is a preliminary version. For now, my code compiles, but it is still not a true Mitra-15 simulator; rather, it is a tentative effort. Many thanks to Pascal Chour for the very useful documentation available on his website: https://www.pascalchour.fr/ressources/cii/mitra15.htm
As my C is rusty (pun is intended) I started with an existing SDS 940 simulator for SIMH and slowly modified it towards Mitra-15's characteristics.
The Mitra-15 is a microcomputer that features interesting concepts, such as the ability to program input/output peripherals using microcode, instead of using an external mechanism such as DMA. https://en.wikipedia.org/wiki/Mitra_15
The Mitra-15 was a 16-bit minicomputer developed by CII (Compagnie Internationale pour l'Informatique) in the early 1970s. It was widely used in industrial automation, scientific computing, education, and military applications. I never programmed on Mitra-15, but I learned CS on a CII 10070 and later I worked at France Telecom which had telephone exchanges piloted with the Mitra family.
Although it was once widespread in France, very little software and documentation has survived. This project contributes to the preservation of this important part of computing history.
This Mitra-15 simulator is intended to eventually include:
- System and optional instructions - Extensive comments describing the original hardware behavior - SIMH console support - Memory management - Interrupt, fast interrupt, suspensions and trap systems * printer * analogic interface * punched_tape * DRI fixed disk * sagem fixed disk * card reader * magnetic tape reader - Various I/O devices, but I lack documentation for many of those peripherals: * asynchronous channels * synchronous channels * fast channel multiplexed * fast channel ADM (no idea what it is) * IOPs (if it's not the same as asynchronous channels).
To this day I did:
search for and analyzed the few remaining documents (see /doc folder).
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