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.

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:
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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

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
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  • 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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What's the most recent MS-DOS that's compatible with the Compaq Portable 1?

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    What's the most recent MS-DOS that's compatible with the Compaq Portable 1?

    I have a Compaq Portable I from 1982. Apparently, they originally shipped with MS-DOS 1.1.

    Does anyone know what is the most recent version of MS-DOS that would still be compatible with the machine? It has no Hard Drives, only two 5.25" floppy drives.

    Well, in theory, you can run any version of DOS right up to 6.22 on a floppy-only system. But the size of a 6.22 system compared to a 360K-drive box will impose severe limitations on what you can do.

    I'd either get a hard drive card, such as our own XTIDE, or stick with MS-DOS no later than 3.3.
    Reach me: vcfblackhole _at_ protonmail dot com.


      Is this the interface that Hargle was working on ? A google for it came up mostly for an app to predict Tides.
      Economics isn't a real science. It's an evil art designed for the rich.


        You might have more luck searching for it as XT-IDE, or just try searching the forums here. I know that bare boards are still available, but it'll probably be a while before anyone's ready to send some out in kit form again...


          If I could get a bare XT-IDE board that's already etched and drilled, then I'd be able to gather the components and assemble it myself. I have the equipment for soldering components, but I don't a drill.

          EDIT: I also have an Arduino Uno, which will allow me to burn the EEPROM.


            Wait, though. Would the XT-IDE controller definitely work with the Compaq Portable? I'm still rather new to vintage computers. :P


              I don't see why not--it works with IBM 5150s (providing they have the later revision BIOS).
              Reach me: vcfblackhole _at_ protonmail dot com.


                The XT-IDE works in a portable I. I've done it with mine.


                  Originally posted by Chuck(G) View Post
                  or stick with MS-DOS no later than 3.3.
                  Good advice right there - It's why I stick with DOS 2.11 on my Tandy 1000's. Nothing like having a fully working DOS up and running on a 640k machine, and having 612k reported as free memory after startup with joystick.sys and zansi.sys loaded.
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                    Also hard disk performance can be better using FAT-12 with many less buffers allocated, as the FAT is so much smaller (and hence it's more likley that required FAT reads will be serviced from the DOS buffer pool).


                      I know I ran DOS 5 on 4.77 MHz 8088s, and I may have even run DOS 6 on them, but didn't really see any benefit. 386s and up can benefit from DOS 5 and 6, and arguably 286s can benefit in some cases. But since 8088s don't have upper memory or high memory, all they really get is bloat. So I'd stick with DOS 3.3 or older and add a third-party text editor and whatever other utilities you need.

                      One thing you can do to ease the pain of only having two 360K drives to work with is to run UPX on the .com/.exe files to pack them down some. UPX has a --8086 switch to keep it compatible with older PCs. I would suggest running UPX from a modern machine though; it'll take a lot less time. You can find UPX at
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                        I agree and disagree with the DOS 3.3 or earlier recommendation. For most applications you are right..... DOS 3.2 or so is probably the best. BUT if you are using the machine with INTERLNK and want it to play nice with machines that have later versions, it won't work so well.

                        I ran into some problems when I INTERLNK'd my 5140 running 3.2 to my junkbox server which was running 5.0. The solution was easy though.... just boot the 5140 with 5.0.

                        OTHER than that scenerio.... I'd stick with ~DOS 3.2.