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
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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.
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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.

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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IMSAI Copies MITS Bus?

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    IMSAI Copies MITS Bus?

    Thomas "Todd" Fischer posted the following on comp.os.cpm. I thought it was worth cross-posting.

    This discussion seems to still have legs, so here's a rather profound statement from Joe Killian in the first-ever contact between him and Ed Roberts last Monday regarding the attainment of "critical mass" of acceptance for the bus standard developed by Roberts and Bill Yates:

    "Your card size, bus connector and signal definitions were copied, by IMSAI, Processor Tech, and countless others, either for complete systems or add-in boards. This was the sincerest form of flattery, done because I and others saw supporting your design as the best business path to pursue. I do think that this support in the form of add-in cards and alternate platforms using the same bus was fortuitous for all of us, in that it snowballed into the fledgling industry's standard. I've always sort of felt that my choice of using your bus, and thus IMSAI quickly being out there as a second MITS compatible machine, tipped the balance on the part of all the others wanting to enter the microcomputer market.

    "Without such a standard, I would guess that neither MITS nor the industry would have taken off nearly so quickly. Nothing else from your machine was copied in the design of the IMSAI (save the use of the 8080 chip, of course). By contrast, I had the dubious privilege along the way of examining a competing chassis that copied my IMSAI chassis right down to holes I put in for options that we never used."

    Ed Roberts responded back to Joe about the observation that on the original Altair processor board, there are no signal line vias between the
    8080 processor chip and the connector. Joe asked if this was done to ease the layout task. Ed responded:

    "Bill Yates and I personally did the PC layouts. And yes the layouts were done bas[ed] on what was the easiest and quickest not on what was the most logical.

    We were grossly under staffed, overwork[ed] and essentiall[y] bankrupt at the time we did the Altair.

    Maybe this will give you a view of my perspective of early events.

    Regards, Ed"

    So now you can reflect back when dealing with issues of bus interface next time you're working on your own "time machine", regardless of it's name!


    -Thomas "Todd" Fischer
    The Vintage Computer and Gaming Marketplace
    The Vintage Computer

    IMSAI vs. Altair

    IEEE 696 as a standard for s-100 systems were not standardized until after Altair was about done as a company. For this reason there was only hit or miss direct compatibility but close enough given the times. My point is compatibility then is not the same as compatibility now. Just my humble opinion on this subject.
    @ BillDeg:
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      MITS/IMSAI S-100 Bus

      If I remember rightly, there was a great deal of criticism of the S-100 Bus in the engineering community. I can't remembee details, but some of the complains were: Too noisy, To wasteful of pins, Not carefully laid out and many others. However, as was pointed out, it sold in hge quantities! Some signals wwere added even after the Altair and IMSAI were well established. For example, Processor Tech added (I think) the "PhANTOM" signal on pin 67. Anyway, somewhere arond here I have a copy of the proposed IEEE standard as submitted by George Morrow and someone else. It finally got accepted but it was dead by that time. I have always wondered just how long it might have lasted as processor speeds grew faster and faster. I think the fastest cpu chip to make it to the S-100 bus was the 8086, or maybe the Z-80 or Z-8. But we are talking about under 10 MHZ cloxk speed.
      Pioneer Purveyor of Personal Processing Power