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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.


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.


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.



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.


"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.

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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Any interest in a PCjr CPU upgrade board?

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  • Airxx
    replied
    Bid posted. I'm very excited at the prospects of my Jr getting an upgrade.

    Leave a comment:


  • MicroCoreLabs
    replied
    The Spartan-6 I'm using doesn't have enough RAM either! So I'm using an external 512Kx8 SRAM.

    Leave a comment:


  • bitfixer
    replied
    I'm just discovering this thread, very nice project! I may be interested in trying to adapt the design to the Tandy. Just got an EX that I have been looking forward to playing with. Also have a bunch of ice40 fpgas I use for another project - although they definitely don't have enough RAM for 512k. Maybe I can use two of them.. in any case that will be added to the project queue.

    Leave a comment:


  • MicroCoreLabs
    replied
    Well, it is available in a sense. All of the project files are on GitHub, so someone could easily port this design to support the Tandy. My understanding is that the differences are just in a mapping of expanded memory which is slightly different than the IBM XT.

    I wish I could build a board to support the Tandy, but there are just so many projects I can tackle at a time!

    Leave a comment:


  • kc8eyt
    replied
    Originally posted by MicroCoreLabs View Post
    I have listed the next batch of five MCL86jr boards on Ebay: https://www.ebay.com/itm/154425005735

    I listed them for $1,000 so VCF members could get the first shot at them before someone else gets them.

    If you offer $90 then I will accept!

    Thanks!
    ​​​​​​​-Ted
    Man, I wish something like this were available for my Tandy 1000 EX and HX systems. I've upgraded them to V20 but this would be way better!

    Leave a comment:


  • RiverBoa99
    replied
    Originally posted by MicroCoreLabs View Post
    I have listed the next batch of five MCL86jr boards on Ebay: https://www.ebay.com/itm/154425005735

    I listed them for $1,000 so VCF members could get the first shot at them before someone else gets them.

    If you offer $90 then I will accept!

    Thanks!
    ​​​​​​​-Ted
    Bid made. Thanks for offering a new batch!

    Leave a comment:


  • MicroCoreLabs
    replied
    I have listed the next batch of five MCL86jr boards on Ebay: https://www.ebay.com/itm/154425005735

    I listed them for $1,000 so VCF members could get the first shot at them before someone else gets them.

    If you offer $90 then I will accept!

    Thanks!
    ​​​​​​​-Ted

    Leave a comment:


  • maxtherabbit
    replied
    Originally posted by animekenji View Post
    Then it's not worth the time that goes into designing it, either, if only 5 people are going to buy it.
    that would be true if the purpose behind designing it was to create a product for sale

    you are (intentionally?) missing the fact that most of these cottage designs are made for the benefit of the designer out of love for the hobby

    Leave a comment:


  • animekenji
    replied
    Originally posted by maxtherabbit View Post
    Tooling up for a production run of a hobby project sizable enough to make profit even relevant is a massive undertaking. You clearly don't understand that. Thinking about "limiting" one's market when the product itself is this niche is somewhat comical. You should be grateful that anyone even cares enough about this stuff to design these projects. Expecting them to cater to your convenience sounds reasonable when you talk about being willing to pay for it, but the reality is that on super short runs the amount they would have to charge to truly compensate themselves fairly for the time invested in setting up the production would be astronomical.
    Then it's not worth the time that goes into designing it, either, if only 5 people are going to buy it.

    Leave a comment:


  • maxtherabbit
    replied
    Originally posted by animekenji View Post
    I didn't say that "nobody" would want it. What I'm saying is that you severely limit your market when you do it that way because many people who might otherwise buy it in pre-assembled form, won't buy it as a kit or a blueprint if they don't have the time or the skill to assemble it themselves. If they are pre-assembled, they would be willing to pay the extra for the convenience of it being plug in and go.
    Tooling up for a production run of a hobby project sizable enough to make profit even relevant is a massive undertaking. You clearly don't understand that. Thinking about "limiting" one's market when the product itself is this niche is somewhat comical. You should be grateful that anyone even cares enough about this stuff to design these projects. Expecting them to cater to your convenience sounds reasonable when you talk about being willing to pay for it, but the reality is that on super short runs the amount they would have to charge to truly compensate themselves fairly for the time invested in setting up the production would be astronomical.

    Leave a comment:


  • animekenji
    replied
    Originally posted by MicroCoreLabs View Post
    I agree that nobody wants projects like this in kit form.

    I just received word that the five boards I had built are finished and will be shipped by PCBWay this week. I will reach out to the folks who requested one once they are programmed and tested.

    Hopefully these five boards are enough for the current interest, but if anyone else wants one, please PM me and I will kick off another build.
    I didn't say that "nobody" would want it. What I'm saying is that you severely limit your market when you do it that way because many people who might otherwise buy it in pre-assembled form, won't buy it as a kit or a blueprint if they don't have the time or the skill to assemble it themselves. If they are pre-assembled, they would be willing to pay the extra for the convenience of it being plug in and go.

    Leave a comment:


  • MicroCoreLabs
    replied
    Originally posted by animekenji View Post
    It's a dead end unless it's sold as a fully assembled product. Not many people can, or care to, have to assemble it themselves. I always hate it when someone creates something amazing, and then will only sell you plans or a parts kit.
    I agree that nobody wants projects like this in kit form.

    I just received word that the five boards I had built are finished and will be shipped by PCBWay this week. I will reach out to the folks who requested one once they are programmed and tested.

    Hopefully these five boards are enough for the current interest, but if anyone else wants one, please PM me and I will kick off another build.

    Leave a comment:


  • animekenji
    replied
    Originally posted by VERAULT View Post
    Yes this project seems to ne a dead end unless its made opensource or sold as a kit.
    It's a dead end unless it's sold as a fully assembled product. Not many people can, or care to, have to assemble it themselves. I always hate it when someone creates something amazing, and then will only sell you plans or a parts kit.

    Leave a comment:


  • MicroCoreLabs
    replied
    Originally posted by psergiu View Post
    You could, in theory, with a side-car to ISA adapter, plug in a ISA SBC, pull out the 8088 and built-in RAM and disable video to not conflict with the SBC and treat the whole PCjr as a ISA peripheral
    I still think it's easier just to replace the 8088 with the SBC. Then you have access to everything.

    Leave a comment:


  • psergiu
    replied
    Originally posted by animekenji View Post
    Do you think it would be possible to do something like a SBC on a sidecar that only uses the PCJr to pass it's signals to the peripherals attached to it?
    You could, in theory, with a side-car to ISA adapter, plug in a ISA SBC, pull out the 8088 and built-in RAM and disable video to not conflict with the SBC and treat the whole PCjr as a ISA peripheral

    Leave a comment:

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