Image Map Image Map
Page 2 of 2 FirstFirst 12
Results 11 to 16 of 16

Thread: minimal F-11 SBC ?

  1. #11
    Join Date
    Dec 2010
    Location
    Colorado Springs
    Posts
    174

    Default

    Thanks Dave!
    However, I'm thinking that those docs are describing the LSI-11, not the F-11. I just checked, and some of the LSI-11 chips actually have the 1600-series part number on them.
    Am I confused? Or, is the assertion that the F-11 is also a WD design using the same architecture?
    I've got some F-11's that have an "AMI" brand marking (some just say "DEC").

    Pete

  2. #12
    Join Date
    Jun 2012
    Location
    UK - Worcester
    Posts
    3,551

    Default

    >>> I thought the LSI was the MCP-1600 but the F11 was DECs own design?

    Pass... I may have been meaning the LSI as opposed to the F-11 of course...

    >>> Thanks for the reference to the Soha & Pohlman paper - looks like the next step after the LD12. :>)

    Not likely !

    I have a few days off (Mondays and Fridays) so I am working on the LD12 a bit more (in between real work of course)...

    Incidentally, do you know what size of jack socket the 'logic probe' connector is? I am assuming a 'mono 1/4"' from the photographs? This is the last part of the puzzle for the front panel - although I have to re-lay the FP out (yet again) as I require a bit more space.

    Dave

  3. #13
    Join Date
    Jun 2012
    Location
    UK - Worcester
    Posts
    3,551

    Default

    A bit more investigation and I can confirm you are correct.

    The F-11 chip is the "11/23" which is a DEC part.

    The LSI-11 is the DEC/WD MCP-1600 parts.

    Sorry for the confusion .

    Dave

  4. #14
    Join Date
    Sep 2019
    Location
    Zurich, CH
    Posts
    113

    Default

    Quote Originally Posted by cbscpe View Post
    I thought the LSI was the MCP-1600 but the F11 was DECs own design?
    Correct. And also, the MCP-1600 cannot, out of the box, run PDP-11 programs. For that you need the DEC microcode chip. It's just that the LSI-11 was based on the MCP-1600, with DEC microcode.

    See https://en.wikipedia.org/wiki/PDP-11#LSI-11

    The LSI-11 was used in the PDP-11/03.
    The F-11 was used in the 11/23 and 11/24, the Pro-325 and Pro-350, as well as various embedded stuff.

  5. #15
    Join Date
    Apr 2017
    Location
    Switzerland
    Posts
    287

    Default

    Quote Originally Posted by bqt View Post
    Correct. And also, the MCP-1600 cannot, out of the box, run PDP-11 programs. For that you need the DEC microcode chip. It's just that the LSI-11 was based on the MCP-1600, with DEC microcode.

    See https://en.wikipedia.org/wiki/PDP-11#LSI-11

    The LSI-11 was used in the PDP-11/03.
    The F-11 was used in the 11/23 and 11/24, the Pro-325 and Pro-350, as well as various embedded stuff.
    But the microcode was in standard MCP 1600 microcode ROMs, so you could actually read them and disassemble. would be interesting to have a look how they implemented a PDP-11 in MCP-1600 microinstructions. I will ask a collegue who got two LSI11/02 to borrow one so I can copy the ROM.
    For more information about my projects see https://www.5volts.ch

  6. #16
    Join Date
    Dec 2010
    Location
    Seattle, WA
    Posts
    1,946

    Default

    Quote Originally Posted by cbscpe View Post
    But the microcode was in standard MCP 1600 microcode ROMs, so you could actually read them and disassemble. would be interesting to have a look how they implemented a PDP-11 in MCP-1600 microinstructions. I will ask a collegue who got two LSI11/02 to borrow one so I can copy the ROM.
    Eric went through that exercise with the LSI-11 microcode 4 year ago. One complication is that there are application specific translation PLAs in the control chip which at the time had not yet been dumped. Just the microcode alone is not sufficient for complete knowledge of the implementation.

    Microcode, DEC LSI-11
    https://github.com/brouhaha/lsi11uc

    Disassembler for Western Digital CP16xx/WD21xx Microcode
    https://github.com/brouhaha/cp16dis

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •