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Any interest in a PCjr CPU upgrade board?

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  • Eudimorphodon
    replied
    Originally posted by MicroCoreLabs View Post
    Regarding the Tandy without DMA... I dont have a system to test it on but I do support the necessary signals (as least I believe I do), so it should probably work. I have also never tried the MCL8jr in a system running faster than 4.77Mhz, so Im not sure if this would be an issue. I dont see why not, but I wouldn't want anyone to purchase one only to find out it doesn't work!
    The Tandy 1000 has an upside-down memory map compared to the PCjr, so unless your device accommodates that it's not going to work "properly" in a 1000. (The 1000 requires expansion memory to be placed starting at 00000h; it counts up from zero in 128k pages up to either 512k or 384k, depending on whether we're talking about an original 1000/1000A or a 1000EX/HX, and then maps its own 128k/256k built-in memory at the end under the 640k mark. If you put 512k of RAM set up for a PCjr into one, IE, starting at 20000h, it's not going to bother counting it because it'll see no memory at 00000h and assume that's where the built-in RAM, which for the initial phase of POST is paged up to Bxxxxh, needs to go.) I'm sure moving the RAM block would be a trivial change given this is an FPGA, but it'd need to be done.

    Leave a comment:


  • MicroCoreLabs
    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?
    So you're saying use some other CPU/SBC to directly access the computer's peripherals as-is it was the 8088? Neat idea!

    This may be possible with a new project idea I am toying around with: http://www.vcfed.org/forum/showthrea...board-debugger

    Rather than just use the Teensy's CPU to run a test program it could be used to simply control the computer as the 8088 would!

    Leave a comment:


  • animekenji
    replied
    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?

    Leave a comment:


  • MicroCoreLabs
    replied
    PCBWay has been a bit slow due to holidays and demand for their services, so I'm still waiting for the five boards I ordered two months ago! I have them assemble the boards so this adds to the delay.

    Please send me a PM if you would like a copy of the board. Im sorry I did not see the requests in this forum thread at the time I made the last order!

    The MCL86jr is open sourced on GitHub, so the schematics, PCB files, FPGA source, and binary are all available, however I appreciate that people would prefer it sold assembled, programmed, and tested rather than building it on their own. I will make a larger batch next time, so please send me a PM so I can keep track, or reach out to me through MicroCoreLabs.com.

    Regarding the Tandy without DMA... I dont have a system to test it on but I do support the necessary signals (as least I believe I do), so it should probably work. I have also never tried the MCL8jr in a system running faster than 4.77Mhz, so Im not sure if this would be an issue. I dont see why not, but I wouldn't want anyone to purchase one only to find out it doesn't work!

    Leave a comment:


  • VERAULT
    replied
    Yes this project seems to ne a dead end unless its made opensource or sold as a kit.

    Leave a comment:


  • dhau
    replied
    Will this work in Tandy systems that don't have DMA?

    Leave a comment:


  • mangolefroot
    replied
    If you make more than I am definitely interested.

    Leave a comment:


  • Airxx
    replied
    Well, I cannot make heads nor tails of the PCBWay website and can only make the physical boards at OSH Park with no assembly... so I guess i'm out on this. Too bad, as it really sounded interesting.

    Leave a comment:


  • Airxx
    replied
    Originally posted by MicroCoreLabs View Post
    Hi,

    Thank you for the interest in the MCL86jr! Yes, I sold four of the initial five boards that were made and so far their owners seem to be happy with them!

    I don't have a solution for mass production and distribution at this point, however 100% of the development files (FPGA and PCB) are available on GutHub for anyone to produce more boards. The total cost for PCBWay to manufacture and assemble five boards was around $250.

    Here is the GitHub project: https://github.com/MicroCoreLabs/Pro...master/MCL86jr

    Thanks again!
    -Ted
    Is there any way to split out the PCjr stuff from the other projects? The file is pretty large and I'm not having much luck with getting just the needed files to a PCB maker. Seems they all want a zip file (which your is), but your file has multiple projects inside which I do not want to make. Was going to try OSH Park or PCBWay and see what kind of price they would give me (a newbie) for a few boards. This may be a dumb request, and if it is I apologize in advance as I really don't know much about making PCBs. At all.

    Leave a comment:


  • psergiu
    replied
    PCBWay just makes the empty boards or also adds & solders all the components in that price ?
    Will they also upload the code on the Xilinx so it's ready to plug-n-play ? If not, what tools/JTAG adapter does one needs for that ?
    I've never ordered anything from a PCB manufacturer and never programmed anything more complicated than an Arduino so i have no idea ...
    Thanks a lot !

    Leave a comment:


  • Airxx
    replied
    I believe I'd be interested in this project as well. I have zero experience in making PCBs or trying to order them however. If anyone who does know what they are doing decides to organize an order, I'd welcome a head's up and can Paypal my funds upon order. I should probably start learning how to do this as it does seem like a commonly needed skill for this hobby, lol.

    Leave a comment:


  • MicroCoreLabs
    replied
    Hi,

    Thank you for the interest in the MCL86jr! Yes, I sold four of the initial five boards that were made and so far their owners seem to be happy with them!

    I don't have a solution for mass production and distribution at this point, however 100% of the development files (FPGA and PCB) are available on GutHub for anyone to produce more boards. The total cost for PCBWay to manufacture and assemble five boards was around $250.

    Here is the GitHub project: https://github.com/MicroCoreLabs/Pro...master/MCL86jr

    Thanks again!
    -Ted

    Leave a comment:


  • VERAULT
    replied
    I thought you were going to reach out to us to sell them direct. I had no idea you were posting them on ebay

    Leave a comment:


  • ajacocks
    replied
    Iím definitely interested, as I believe I mentioned, before.

    - Alex

    Leave a comment:


  • Jjona5
    replied
    Would love to get one if you make more!

    Leave a comment:

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