• How’s the project coming? I keep looking at my stack of disks and wishing I could transfer them. Is there some sort of WIP package that’s downloadable so I could go ahead and build one as it is?

  • Hi Phil.

    There’s no downloadable package perse, because the software needs a few touches still to become usable.

    If you are seriously interested in building this, I can give you a place to start. I’ll warn you in advance that this is builder-beware stuff, it’s not ready for primetime as I see it.

    Hardware-wise, here’s what you need:

    Parallax SX28 proto board ( )

    Some way to program the SX28, namely the SX-KEY (which would probably make sense bought in ) You could potentially just buy the SXKEY itself,

    Power supply for the board ( )

    The USB2SER development tool ( )

    USB cable ( )

    Ramtron FRAM, specifically FM25256(g or no-g extension ok.( )
    You can probably request free samples using their online form.

    IDC 34-pin male to breadboard adapter ( )

    Generic PC 3.5″ floppy drive, preferably Samsung SFD321B, ( )

    Generic floppy cable, no pins swapped, everything straight thru.

    Assortment of low value resistors, namely 1k and below.

    Probably also want some male header pins if hardware debugging becomes necessary. ( or )

    That should be about it. My plan down the road would be to setup some type of programming “service” at low cost so that people not interested in SX programming wouldn’t need to plunk down for the programmer. Because the firmware is not stable, and minor changes are likely to come, this makes little sense now.

    I *need* to make some necessary changes to the java code base before I distribute it, because there are some things to do that would enable it to work properly. I expect to make those changes soon.

    I’ll keep you updated.


  • Note that at current prices, these odds and ends come to roughly $200 + shipping/handling, which will probably add another $30. So perhaps $250 shipped.

    I recognize that this is NOT insignificant, and while the enjoyment/challenge/rewards of this project FOR ME is well worth it, it might not be for the next guy. This doesn’t include older stuff I bought that is obsolete, the $400 logic analyzer, etc etc.

    I don’t consider this practical AT THIS POINT, but I do intend on setting something up to eliminate some of the larger costs. Certainly just getting rid of the $100.00 programming kit would really help.

    Unless you are a DIY project electronics enthusiast type, going to and their catweasel might make much more sense, I don’t know.

  • Hmm…I’ve never been afraid of scratchbuilding electronics (I’ve even made my own PC boards), but investing in all the development tools and programmer for one project is cost-prohibitive. I’ve looked at the Catweasel but, honestly, it does far more than I’ll ever want to do.

    I’ll wait to see what you come up with, I ‘spose. Thanks for the detailed response!

  • I didn’t mean to scare you or otherwise underestimate your abilities. Most likely, if you were even interested in this to begin with, then you have the required skills. And even if one doesn’t have the skills, just a strong desire and due diligence will bridge the gap.

    With all this being said — I really think this is easy. All you need is some time and some basic soldering skills. I guess attaching the surface mount memory to the PCB requires a steady hand, good solder, and a good soldering iron. The memory is only SOIC-8 pin, so it’s really not a super fine pitch, and 8 leads isn’t too tough. It was my first surface mount job, and I did it correctly the first time!

    My end goal would be to offer a parts kit, perhaps in conjunction with Parallax, that would include everything necessary, even a pre-burned SX28 board. I EVENTUALLY want to do a custom PCB, but that’s pretty far out there. For now, their $10.00 prototype board is really nice, good value.

    Thanks for the continued interest.