Forum Rules and Etiquette

Our mission ...

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.

This forum has been around in this format for over 15 years. These rules and guidelines help us maintain a healthy and active community, and we moderate the forum to keep things on track. Please familiarize yourself with these rules and guidelines.

Rule 1: Remain civil and respectful

There are several hundred people who actively participate here. People come from all different backgrounds and will have different ways of seeing things. You will not agree with everything you read here. Back-and-forth discussions are fine but do not cross the line into rude or disrespectful behavior.

Conduct yourself as you would at any other place where people come together in person to discuss their hobby. If you wouldn't say something to somebody in person, then you probably should not be writing it here.

This should be obvious but, just in case: profanity, threats, slurs against any group (sexual, racial, gender, etc.) will not be tolerated.

Rule 2: Stay close to the original topic being discussed
  • If you are starting a new thread choose a reasonable sub-forum to start your thread. (If you choose incorrectly don't worry, we can fix that.)
  • If you are responding to a thread, stay on topic - the original poster was trying to achieve something. You can always start a new thread instead of potentially "hijacking" an existing thread.

Rule 3: Contribute something meaningful

To put things in engineering terms, we value a high signal to noise ratio. Coming here should not be a waste of time.
  • This is not a chat room. If you are taking less than 30 seconds to make a post then you are probably doing something wrong. A post should be on topic, clear, and contribute something meaningful to the discussion. If people read your posts and feel that their time as been wasted, they will stop reading your posts. Worse yet, they will stop visiting and we'll lose their experience and contributions.
  • Do not bump threads.
  • Do not "necro-post" unless you are following up to a specific person on a specific thread. And even then, that person may have moved on. Just start a new thread for your related topic.
  • Use the Private Message system for posts that are targeted at a specific person.

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.

Here are some obvious examples of when you should not reply to a thread and use the PM system instead:
  • "PM Sent!": Do not tell the rest of us that you sent a PM ... the forum software will tell the other person that they have a PM waiting.
  • "How much is shipping to ....": This is a very specific and directed question that is not of interest to anybody else.

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

If you see spam, a wildly off-topic post, or something abusive or illegal please report the thread by clicking on the "Report Post" icon. (It looks like an exclamation point in a triangle and it is available under every post.) This send a notification to all of the moderators, so somebody will see it and deal with it.

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
  • Use Google, books, or other definitive sources. There is a lot of information out there.
  • Don't make people guess at what you are trying to say; we are not mind readers. Be clear and concise.
  • Spelling and grammar are not rated, but they do make a post easier to read.
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Cheap homebrew ISA->PC104 adapters

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    Cheap homebrew ISA->PC104 adapters

    I've been playing with PC104 CPU boards recently and was frustrated by how expensive it is to plug an ISA card into them. Most adapters are more than $100 and that seems ridiculous when you could probably make your own DIY adapter reasonably easily using IDC connectors and ribbon cable.

    But I was doing a big PCB order anyway so decided to spend a couple hours knocking up some boards, cost each less than $20 :

    The small one leaves access to the main board but means that the card lies outside the PC104 footprint :

    The large one sort of folds the ISA card back on top of the PC104 board and is probably more useful if putting the assembly in an enclosure :

    I tested them and they work great! Here's a video of my old Ensoniq Soundscape Opus running on an Advantech PCM-5890 :

    Gerbers for the boards can be found here (your fab house will need to be able to do 5mil trace/space) :

    And the source CAD files are in Altium Circuitmaker's cloud :

    This is just the first revision so don't go plugging anything irreplacable into it until I've done more testing, but they seem to work perfectly for me on all the cards and motherboards I've tried. There's no decoupling capacitors or anything since I figure most ISA cards will have plenty on board, and the traces aren't very long anyway. The power traces are thicker than the data traces but they could perhaps be even thicker, I don't know how much current an ISA slot is expected to cope with.

    The designs are public domain, do with them as you wish.

    ooh, this is quite interesting
    I've got an ISA SBC that works great, but the onboard video chipset is dead, so I have to use an external vga card. This will be of great help, if I ever get around to doing anything with that.
    Current favorites: IBM 5160 (EGA+Hercules+PGC, 8 floppy drives, XT-IDE), DCC D-116 (Nova 1200 clone), ASR 33 Teletype, PDP-8/I (lots of issues, restoration underway)
    Wishlist: IBM 5161 (expansion chassis), Diablo 31/RK02/RK05 or equivalent, Data General equipment, and the meaning of life.


      Well Done!

      I've got some of those expensive ISA/PC104 conversion boards- bought 20+ years ago. These look good.

      Have you considered selling them?

      I've been updating the PC104 CPU boards on some of my older systems, bought the ICOP VortexDX3 based PC104 boards- at $70 each. So far, they are running DOS, Pharlap DOS, Win98, and Win XP.


        Originally posted by BrianS View Post
        Have you considered selling them?
        Hmmm.... I don't really have the time to manually assemble very many and I don't think there would be enough demand to do a proper production run (would need to be in triple digit quantities to make it worthwhile really).

        If anyone deperately wants one though get in touch, I do have half-a-dozen unpopulated boards that I could be persuaded to assemble for maybe $40 each.


          Originally posted by BrianS View Post
          Have you considered selling them?
          Interesting idea but I don't think there'd be enough demand to do a proper production run, and I don't have time to manually assemble them.

          That said though if anyone wants one get in touch, I could maybe be persuaded to build a few.


            Man, this is godsend! I'm glad I found your site Rasteri. I'd like to buy a couple of them if you still have some extra left. I can populate the boards myself too, either way.