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:
  • "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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64-256k --> 256-640k

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  • k2x4b524[
    I have this mod on my remaining XT-Board, works great, but my 8-bit card doesn't like it very well, so i roll CGA and it's flawless

    Originally posted by ibmapc View Post
    Why stop at 640K? With 36 256k chips (all 4 banks) and a custom programmed GAL with adapter in u44, you can have 640K of base memory and up to 256k(depending on video card etc...) of Upper Memory that can be used as UMB to LOADHI drivers to free up conventional memory. If interested, I can supply the GAL and adapter for the cost of shipping. READ HERE FOR MORE INFO

    Leave a comment:

  • josephdaniel
    That would be great! I will send you a PM.

    Leave a comment:

  • ibmapc
    Why stop at 640K? With 36 256k chips (all 4 banks) and a custom programmed GAL with adapter in u44, you can have 640K of base memory and up to 256k(depending on video card etc...) of Upper Memory that can be used as UMB to LOADHI drivers to free up conventional memory. If interested, I can supply the GAL and adapter for the cost of shipping. READ HERE FOR MORE INFO
    Last edited by ibmapc; July 18, 2013, 05:39 PM.

    Leave a comment:

  • josephdaniel
    ok so I figured out that I already have 10 256k chips on my expansion board (I will get the other 8 that I need fom ebay) the rest of the chips in my system are all 64k chips. I found the chip that goes in u84, it is the 74LS158 multiplexer chip which is avalable very cheap

    Leave a comment:

  • josephdaniel
    Thanks guys,
    If I can't find a pre-made BIOS I am probably fine without it... I don't really want any multi I/O cards as I just bought all of these cards and then I saw this internal modem that I *had* to have. Famous last words) if I ddin't see it I woulden't be having this problem... Thanks for the tip on the RAM chips though

    Leave a comment:

  • Maverick1978
    replied has the BIOS that you need

    Leave a comment:

  • SpidersWeb
    You'll be able to download the binary file of that ROM image from minuszerodegrees
    Thanks to modem7.

    You'll want to have an EPROM writer, UV eraser, and some spare chips handy (unless someone here volunteers to send some pre-written).
    Although I've never needed to upgrade the BIOS on an XT, and I use 101 key clone XT keyboards without problems - perhaps mine go in to '83 key mode' or something.

    For the memory situation, have you considered just buying an AST SixPakPlus?
    Replace your serial/parallel card with it - gives you serial/parallel/384KB RAM/battery backup clock - in one slot.
    One slot is key, because you basically replace your current serial card with it, so no space is lost internally and you get a 640KB XT that can remember the time!

    But if you want to go ahead, 41256 chips are easily found on ebay (36 of them + I'd get a few spares). Not sure about U84 sorry, I'm sure someone else here will know.
    Last edited by SpidersWeb; July 18, 2013, 12:13 PM.

    Leave a comment:

  • josephdaniel
    started a topic 64-256k --> 256-640k

    64-256k --> 256-640k

    I have an XT from November of 1984 with a 64-256k motherboard in it that I want to modify to the newer 256-640 motherboard. I ran into two small problems where can I get the 256K RAM chips and where can I get the multiplexer chip that goes in u84? I am fine with soldering (Antique electronics is another hobby of mine) pin 1 and 11 on u44
    Note also where might I find the later BIOS that includes support for 101 key enhanced keyboards and boots faster?