CDC 1700 emulator added to SIMH

For those of us, who have never heard of the CD 1700, there is a brief page on wikipedia:

https://en.wikipedia.org/wiki/CDC_1700

And from the announcement on the SIMH mailing list:

For the past couple of years or so, I have been working on a SIMH-based
simulator for the CDC1700 series, a 16-bit system from the mid-1960’s, using
the documentation and software available at bitsavers. It has now sufficiently
stable to allow others to make use ot the software. The base system implements:

  • a 1714 CPU with:
    • 1705 multi-level interrupts and direct storage access bus
    • up to 32KW of memory
    • memory protect system
    • Optional 64KW support
  • 1711-A teletypewriter
  • 1721-A paper tape reader
  • 1723-A paper tape punch
  • 1740 or 1742-30 line printer
  • 1738-B disk pack controller with up to 2 disk packs:
    (853 disk pack – 1.5MW)
    (854 disk pack – 3.0MW)
  • 1733-2 cartridge disk controller with up to 4 drives:
    Each drive has 1 fixed disk and 1 removeable disk:
    (856-2 CDD – 1.13MW per disk)
    (856-4 CDD – 2.25MW per disk)
  • 1732-A or 1732-3 magtape controller with 4 transports

The simulator is able to boot the diagnostic tape (SYSTEM17_SMM_DIAGS.TAP at
bitsavers.org) and successfully execute tests for each of the above
components. Some test sections fail due to various reasons; lack of
documentation, timing issues, feature not implemented etc.

The simulator is also able to boot and install MSOS 5 from an installation
tape (MSOS5_SL136.tap at bitsavers.org) onto a 1733-2 cartridge drive. This
is a copy of a distribution tape provided by CDC to run on a 64KW system at
Exxon.

I would like to thank Doug Gwyn for answering questions about the system
architecture and providing details about specific diagnostics tests and
Al Kossow for for peripheral documentation so that I could get MSOS 5
installed.

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