SD-Cart JR: An MMC/SD card reader cartridge

[Fenyx4]

Here is another debug build which will wait 4 times longer. Could you tell me if it makes any difference?

Sorry, here it is: https://www.raphnet.net/electronique/sd ... debug2.zip

That worked! Kinda. Once. sdpart.com worked once when I used it right after booting up. But if I try it a second time (even immediately) it fails again. Rebooted and tried again and it didn't work.

Here is the output from the one success.

Code: Select all

Card: 74/J' (Transcend) SDC  v1.0
        Serial 38 00 EC CE , OCR: 80FF800
        SD Version 1.0, Byte-addressed
        Sectors: 0x003BD800
        SD-Cart geometry: CHS=244,255,63

Command (? for help): p

Part. 1 : inactive, type=06 (FAT16B)
    CHS: 0,4,4-972,44,44 (0000000FF-00314FCB)
    LBA: blocks 000000FF-003BD7FF

Part. 2 : inactive, type=00 (empty)
Part. 3 : inactive, type=00 (empty)
Part. 4 : inactive, type=00 (empty)


Nice! Maybe I don't see it, but did you drill a small hole to let the activity LED shine through? Or perhaps you simply trimmed the enclosure "lip" near the LED?

Ooo, I hadn't thought about the LED. I'll experiment tomorrow to try to get it visible.
Here are some pics of what I had to trim in case it helps. It was white PLA spray painted with black before the trims so you can see where I made cuts pretty clearly.

https://photos.app.goo.gl/4Qwu6uJ6N4RQggRe9
https://photos.app.goo.gl/jfA1hdZ6iYRnVmYM8
https://photos.app.goo.gl/KMjb51wSrsg2j8p87
https://photos.app.goo.gl/sKBKWbKHUFgGD8VM7

On the base I had to;
1. trim near the screw holes making them thinner
2. trim part of the thin part of the back (I overcut this part)

On the top I had to;
1. trim part of the back both the thin and some of the thick
2. trim a stand thingy that was bumping into C11 on the board. (I think it would be possible to move it)

I should have released a slotted cartridge STL already... I'll try sharing a new STL with a built-in slot in a few days.

That would be great! Wish I could help more. But fear I have no experience with 3d model editing.

[jscrow]

I was able to get a cheap 64mb card to work on my SD-Cart JR using both the device driver and now the boot rom. Using the boot rom, the card is assigned as fixed disk c: and I can read/write with no problems, I can also use fdisk and format/s on the SD card drive with no issues. However, the computer freezes (see pic) every-time I've tried to boot from the SD card using both PC DOS 3.3 and (patched) 5.02 ... I've tried repartitioning and reformatting numerous times with no change, I can't figure it out, I guess I should try another card...

[raphnet]

That worked! Kinda. Once. sdpart.com worked once when I used it right after booting up. But if I try it a second time (even immediately) it fails again. Rebooted and tried again and it didn't work.

Ok, I may need to try several things to diagnose and correct this... so I ordered the same model of card, I hope I'll be able to reproduce the issue!

Here are some pics of what I had to trim in case it helps. It was white PLA spray painted with black before the trims so you can see where I made cuts pretty clearly.

Thanks, this will be an excellent checklist to make sure I don't forget anything while preparing the new model.

I was able to get a cheap 64mb card to work on my SD-Cart JR using both the device driver and now the boot rom. Using the boot rom, the card is assigned as fixed disk c: and I can read/write with no problems, I can also use fdisk and format/s on the SD card drive with no issues. However, the computer freezes (see pic) every-time I've tried to boot from the SD card using both PC DOS 3.3 and (patched) 5.02 ... I've tried repartitioning and reformatting numerous times with no change, I can't figure it out, I guess I should try another card...

It's interesting that read/write works but booting does not... Could you run sdpart.com and show me the output of the card init (done automatically when sdpart.com starts) and the output of the p command?
And just to be sure (I know you wrote that you repartitionned) could you confirm that even after actually deleting and creating a new partition using fdisk on the PCjr and formatting it adequately it still did not boot?

[jscrow]

Yes I've deleted/added/made active DOS primary partitions in fdisk for both 3.3 and 5.02 and then format/s. I tried again and now get an error message when I try to boot DOS 3.3 from the 64mb card (see left pic and error below). I also tried another card with patched DOS 5.02 (right top pic) and get the same freezing at boot (bottom right). I even tried to boot both SD cards in another PCjr (with jrIDE installed) and get the same stuck frozen at "booting from SD..." Otherwise, read/write and access to drive c: works fine... just can't boot.

[raphnet]

Yes I've deleted/added/made active DOS primary partitions in fdisk for both 3.3 and 5.02 and then format/s. I tried again and now get an error message when I try to boot DOS 3.3 from the 64mb card (see left pic and error below). I also tried another card with patched DOS 5.02 (right top pic) and get the same freezing at boot (bottom right). I even tried to boot both SD cards in another PCjr (with jrIDE installed) and get the same stuck frozen at "booting from SD..." Otherwise, read/write and access to drive c: works fine... just can't boot.

Thank you for confirming. I see in the screenshots that the partitions seem fine. Now I wonder how much of the MBR fdisk leaves as-is, even when deleting and creating partitions.. On the DOS 3.3 card, could you try using the 'c' and 'w' commands in sdpart.com to write a new, empty MBR to the card, followed by a reboot, and then fdisk format /s ? Then I will know you have exactly the same MBR code as I do. If this does not work, then there is another difference between your machine and mine that is causing this. It could be the card, but it seems unlikely given that you tried 2 and that its only booting that does not work. My Jr has a total of 256K of memory (128K in a sidecar) + a parallel port sidecar. No other add-ons or mods.

The "Too many drives" error message is quite unexpected, especially if you do not have other drives on your Jr...

[jscrow]

That worked! I ran "c" and "w" in sdpart and then fdisk/format and now DOS 3.3 boots perfectly! So any reason I shouldn't try this with the DOS 5 sd card? I would just have to patch for the jr..which my version of DOS 5 format.com does seamlessly using /s since it has been patched too.

With the SD-Cart, clock cart, and 512k sidecar ... my PCjr test unit now has all the basic features of a jrIDE

[raphnet]

That worked! I ran "c" and "w" in sdpart and then fdisk/format and now DOS 3.3 boots perfectly! So any reason I shouldn't try this with the DOS 5 sd card? I would just have to patch for the jr..which my version of DOS 5 format.com does seamlessly using /s since it has been patched too.

Ah, excellent! Under DOS 5, could you try running fdisk /MBR instead? I suspect you will need to repatch the MBR after doing this.
If fdisk /MBR does not work, then please go ahead and try the "c" and "w" sdpart commands.

Nice setup! Is that a reset button you added on the front? Why is your clock cartridge labelled with a P-touch style label? Is it homemade?

[jscrow]

yes you're absolutely right I should first try running format /mbr ... thanks for all your help!

That's an Integrity Technologies clock cartridge kit that is built and inside one of their shells. Yes it's a p-touch label, I need to design a nice label for the cart.

I received that PCjr unit with a hole drilled in the front so I put in a reset button ... otherwise I don't think I could have ever brought myself to drill into a PCjr case

[jscrow]

I cut up a raphnet cartridge shell to accommodate the boot rom in a socket. I don't think it turned out too bad

[raphnet]

yes you're absolutely right I should first try running format /mbr ... thanks for all your help!

If you get the chance, could you confirm if the DOS 5.0 fdisk /mbr command alone fixed it? I plan to write a few paragraphs about booting and related troubleshooting, and I would like to mention fdisk /MBR as an alternative to the sdpart "c" and "w" commands, but I'd like to be sure it actually works.