Forum Rules and Etiquette

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This forum is part of our mission to promote the preservation of vintage computers through education and outreach. (In real life we also run events and have a museum.) We encourage you to join us, participate, share your knowledge, and enjoy.

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To put things in engineering terms, we value a high signal to noise ratio. Coming here should not be a waste of time.
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Rule 4: "PM Sent!" messages (or, how to use the Private Message system)

This forum has a private message feature that we want people to use for messages that are not of general interest to other members.

In short, if you are going to reply to a thread and that reply is targeted to a specific individual and not of interest to anybody else (either now or in the future) then send a private message instead.

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Why do we have this policy? Sending a "PM Sent!" type message basically wastes everybody else's time by making them having to scroll past a post in a thread that looks to be updated, when the update is not meaningful. And the person you are sending the PM to will be notified by the forum software that they have a message waiting for them. Look up at the top near the right edge where it says 'Notifications' ... if you have a PM waiting, it will tell you there.

Rule 5: Copyright and other legal issues

We are here to discuss vintage computing, so discussing software, books, and other intellectual property that is on-topic is fine. We don't want people using these forums to discuss or enable copyright violations or other things that are against the law; whether you agree with the law or not is irrelevant. Do not use our resources for something that is legally or morally questionable.

Our discussions here generally fall under "fair use." Telling people how to pirate a software title is an example of something that is not allowable here.

Reporting problematic posts

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If you are unsure you may consider sending a private message to a moderator instead.

New user moderation

New users are directly moderated so that we can weed spammers out early. This means that for your first 10 posts you will have some delay before they are seen. We understand this can be disruptive to the flow of conversation and we try to keep up with our new user moderation duties to avoid undue inconvenience. Please do not make duplicate posts, extra posts to bump your post count, or ask the moderators to expedite this process; 10 moderated posts will go by quickly.

New users also have a smaller personal message inbox limit and are rate limited when sending PMs to other users.

Other suggestions
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Amstrad PPC512 / 640 ISA Expansion Board Design

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    Amstrad PPC512 / 640 ISA Expansion Board Design

    Hi all,

    Not sure if this is of interest to many, but while I was searching on how to make this thing, vcfed kept coming up, but with no conclusion.

    It adds 3 ISA slots to the luggable Amstrad via its connector on the rear


    Demo here:

    Gerbers and info here:

    That's a beautiful adapter. If I had an Amstrad PPC640, I would get something like this for the XT-IDE card, sound card, and so on.
    Current retro systems:
    386/486DLC, AMS NotePro Plus DSTN
    Packard Bell Pack-Mate 28 Plus
    Toshiba Satellite Pro 410CDT, 2x IBM ThinkPad 380D (both TFT)
    iMac G3/600 Graphite, iMac G4/800 Lampshade
    YouTube channel:


      Thank you very much, XTIDE is great on it, and with the V30 cpu its quite fast for an XT.


        Wow! I'm trying to repair the internal hd board (the one plugged in the copro socket) since weeks... I will pass to this great external solution!


          Originally posted by aotta View Post
          Wow! I'm trying to repair the internal hd board (the one plugged in the copro socket) since weeks... I will pass to this great external solution!
          You've got an HDD board that plugs into the coprocessor socket? If you're able to make pictures and/or ROM dumps I'd be interested to see them.



            Yes, i've dumped the roms and made some shots. The Rom contains the hd driver on top, then the ROS 2.1 from &H4000, and it's splitted in 2 27C128 eprom.
            The power circuit doesn't work anymore (i had a shorts while testing) but it was only for the +12v and +5v to the special power connector of its 20mb hd.
            There's no PAL/GAL on the board, only 74hcXX and the ROM:



            Attached Files


              Very nice! I've always wondered if I could somehow integrate a XUB boot ROM and a cF reader or a IDE DOM.
              General Failure Reading Drive C -
              Abort, Retry, Ignore?


                Interesting ROMs. It looks as if the first 16k is the hard drive BIOS, and the second 16k is the PPC system BIOS, so they replace the PPC's own ROMs entirely.

                The drive geometry is hard coded rather than any attempt being made to probe it from the drive.

                There are two entry points, at offsets 6 (format hard drive) and 9 (set timeout for spin-down). The timeout appears to be stored in bytes 3Eh / 3Fh of CMOS memory.

                The hard drive itself is a memory-mapped device at segment 0F000h. It looks to me as if it's ATA, with the registers at offsets 0,2,4,6,8,... within that segment. There's also an access at offset 1Ch which may be connected with the spin-down.

                The copyright message is 'Controller Copyright (c) 1989 Bineco'


                  Thank you JohnElliott for the info! but i don't think the ROS mapped in the half ROM is a replacement of the original ROS, and i made a test (when the HDIC worked!) and, without the 40107 / 40108 Roms, the PCC didn't start.
                  I think that, in some way, the memory address is shared from the co-proc lines and the ROM/RAM. Now that the interface is not working, i can't see the ROM at expected C800 location, but noticed some bits differences at F000 when card is mounted. So, probably the roms copied the ROS to make consistence to reading at ROS addresses.
                  But i'm not at all at expert in 8086's machines, so are only my thoughts....


                    Well, i got today the 74hcxx logic ICs and... HDIC 88 is working again! now, since the anonimous original 20mb hd makes strange rumours (and i'd like to replace it with a CD or SD to IDE solution), i'll try to replace the original roms with the Universal XT Bios ones!