Possible SSD for jr-IDE?

[Franko]

BTW, this is the CF adapter I'm using:
https://www.amazon.com/gp/product/B07D7 ... UTF8&psc=1

I have one of those too, and it seems to work fine.

[dpaden]

So I ordered some other flash modules and I got one that gets detected. It's a KingSpec 16GB DOM. I am still waiting on the 40-to-44 pin converter for the others.

I formatted the DOM as follows:
C: 2GB
D: 2GB
E: 2GB
F: Remainder of 8GB
Then I installed MS-DOS 6.22 to C:, did the patch to the boot sector, and installed jrconfig.

When the jr boots, it detects the DOM and attempts to boot it, but I get no further text on the screen for quite some time. I let it go for about 20 minutes.
The drive activity LED blips briefly right when it attempts to boot, then even more briefly blinks once every 3-5 seconds.

Am I doing something wrong? Is it possible I need to provide more power to the DOM? Any ideas?
I am not using any additional power sidecar (I have one but am missing the external power brick for it).

EDIT: I didn't note it, but I also inserted STACKS=0,0 at the top of config.sys.

[dpaden]

I don't think power is the issue. Gave the DOM a separate 5V supply from a bench DC supply...same behavior.
If the patch isn't working as expected, is there any printed output on the screen after "Press [ESC] to enter boot menu" (or whatever that message string is)?

[Brutman]

I haven't had time to look into it, but there might be some boundary issue that hits 16GB drives.

I have a 20GB Maxtor spinning rust disk on my system so I know that larger drives work. But there might be something about 16GB that makes it magic.

(I have to go digging through code .. just short on time at the moment.)

[dpaden]

Have others tried loading the OS on the drive from another x86 machine, then plugging it into jrIDE with success? I wonder if there were any address translation issues in the jrIDE, perhaps the data isn't being accessed the same. If that were the case, loading the OS on the jr might work.

I've been trying to avoid pulling the 5.25" drive from the jr and hooking it to my desktop...but it's probably worth a try.
EDIT: ...so I can write the DOS floppy images to the 360k floppies and boot them on the jr.

[dpaden]

I've ordered a 360k drive. Will write some DOS 3 floppies and boot them directly on the jr in a week or so.
Between all the DOMs I have, that should be able to get something up and running.

[Hargle]

The address translation is identical between a 1GB DOM, a 4GB DOM, 8GB or 16GB or any other size you install because it's a linear conversion from CHS values to LBA values.
That is, DOS is going to store its files starting at (roughly) the beginning of the drive. The beginning of a 1GB drive uses the same CHS<->LBA values as the beginning of a 16GB drive. So it is quite unlikely that this issue has anything to do with the drive size you've attached.

While I have not installed an OS on another machine onto a DOM and then moved it onto the PCjr, I have created and formatted partitions of my DOMs (8GB) and then moved the DOM onto a modern machine to fill them up with files. Once I return the DOM to the PCjr, all the files on any partition I access are readable, which should show that the translation done in the jrIDE BIOS matches the translation on a modern PC.

[Franko]

I have created and formatted partitions of my DOMs (8GB) and then moved the DOM onto a modern machine to fill them up with files.

Sorry for a tangental question, but how do you connect a DOM to a modern machine?

[Hargle]

There are adapters o' plenty that can convert SATA and 40/44 pin ATA devices to USB.

https://www.amazon.com/CoolGear-Drive-A ... B004FF3ETA
http://www.cablesonline.com/usb20tosa40p.html
https://www.newegg.com/Product/ProductL ... Submit=ENE

[Brutman]

The trick becomes the cabling ...

DOMs that are female are designed to plug straight into the motherboard. The USB adapters are female too, as they expect you to be plugging in a drive with pins on it.

There are cables for this; you just need to be aware of the pinout and ensure the pins go to the right row. I believe an early Internet device called the iOpener had a weird setup that used these cables, so look for "iopener ide cable" to get an idea of what is needed.

Or, just keep an old machine around that still has an IDE port on the motherboard ...