jr-IDE weird problem

[jltursan]

Well, I've finally managed to get some free time to test my brand new jr-IDE and I'm facing a strange behaviour.

When I power on the machine, it counts to 640KB, shows the XT-IDE mesagges and reports that no drives 0 & 1 are present (still nothing plugged to the card), then it asks to press [ESC] to go to boot menu. After pressing ESC key, an endless loop of drive letters (and ASCII chars) options start to scroll the display. I can see that the first one is my A: drive; but seems that the keyboard is not read. The led display of jr-IDE shows [E.d.].
If I boot without floppy drive connected, there's no [ESC] key message, instead an "ERRORH" brief message is displayed.

Of course, without the jr-IDE, the PCjr boots flawlessly from the 3.5" drive.

Is jr-IDE compatible with 3.5" drives as boot media?, Am I forced to plug a CF/HD to jr-IDE to be able to boot from floppy if I want to do that?

[jmetal88]

Might be a bug in the BIOS extension. Mike will have to check. It could be something that only happens when no hard drive is connected; I know I never tried to boot my Jr-IDE without a hard drive connected (or at least I never tried to access the boot menu when doing so). See if it'll boot up if you just wait it out without pressing ESC. There is a timeout set up that automatically directs the boot to the floppy drive if no key is pressed.

[jltursan]

Yup, that's it. The PCjr boots from floppy after 4-5 seconds. Thanks!
I've used a PC-DOS 2.1 boot disk without flaws. A MS-DOS 5.0 boot disk freezes the machine, I suposse that I'll need to patch the MS-DOS 5.0 to overcome the PCjr incompatibility, isn't it?-

About the IDE; for now, I've plans to plug a CF+adapter (size from 64MB to 256MB) and install MS-DOS 5.0 (I suposse that it'll be the best OS for this PCjr). To accomplish that, once patched the DOS and booted from floppy, can I create and format a CF FAT16 2GB partition and then invoke a SYS to make it bootable?

[Brutman]

It's a bug in the BIOS but I fixed that one a while ago. You need to pick up the latest version ...

[jltursan]

I can live with it for now, I want to setup first a working system before getting into flashing BIOS and so...

Now, I'm facing a stupid problem, where's IDE connector's pin 1 suposedly located?. I can see a mark in the board (look this drawing) that I suposse is the notch of the connector. Given that the connector is at an angle of 90º, I'm connecting the IDE cable with the red ribbon/pin 1 to the bottom of the jrIDE.

There's also a jumper in the board, named JP1 that gives +5V on pin 20. As I want to power the CF card directly from jrIDE, I've jumpered JP1 (it was open by default); but the boot routine seems that isn't detecting any device. I'm not sure about the IDE-CF converter used, so I'll try with any other before starting to worry

Anyway, must the jrIDE detect the CF card prior to any partitioning or formatting?

[alanh]

That's actually a problem with this version of the board. I actually have a notch mark for the IDE connector, but it is under the right angle connector. Doh. Pin 1 is at the bottom of the card. Sorry. That will be marked more clearly if we ever do another run.

[jltursan]

Hehe, no problem, I guessed it right then. I'll keep testing the IDe-CF adapter, it's a two CF slots model and maybe I'm just simply using the wrong one to plug the CF card...

[jltursan]

Mmmm, tried to patch the IBM DOS 5.0 without success. To clarify things, do I need an IBM DOS 5.0 english version boot disk or I can patch the installation disk 1?. I've patched the later (see session screenshot below) and all looks more or less fine; but the machine doesn't boots at all.

[Brutman]

I assume you are following the instructions posted here: http://www.brutman.com/forums/viewtopic.php?f=3&t=224

The general idea behind the patch is to use part of the error message string and replace it with executable code that sets the correct amount of memory in the BIOS variable that tells DOS how much memory is installed. It then jumps back to where it left off.

You are patching the boot sector of the diskette so any bootable DOS diskette can be used. However, there might be minor differences between the versions of DOS. My version of IBM PC DOS is 5.02. I doubt the boot sector is different, but it is possible. And whatever the differences, the same basic technique applies to any version of IBM PC DOS or MS DOS.

What happens to the machine when it fails - where does it get stuck? Are you also putting STACKS=0,0 in the config.sys file?

If you send me a diskette image of what you have *before* you patch it, I can tell you how to patch it correctly if it is different than what I have posted. I have an imager (dskimage) on the software download page.

Mike

[jmetal88]

I assume you are following the instructions posted here: http://www.brutman.com/forums/viewtopic.php?f=3&t=224

The general idea behind the patch is to use part of the error message string and replace it with executable code that sets the correct amount of memory in the BIOS variable that tells DOS how much memory is installed. It then jumps back to where it left off.

You are patching the boot sector of the diskette so any bootable DOS diskette can be used. However, there might be minor differences between the versions of DOS. My version of IBM PC DOS is 5.02. I doubt the boot sector is different, but it is possible. And whatever the differences, the same basic technique applies to any version of IBM PC DOS or MS DOS.

What happens to the machine when it fails - where does it get stuck? Are you also putting STACKS=0,0 in the config.sys file?

If you send me a diskette image of what you have *before* you patch it, I can tell you how to patch it correctly if it is different than what I have posted. I have an imager (dskimage) on the software download page.

Mike

I'm pretty sure my PC-DOS is version 5.00, and it worked fine with your instructions, so I also doubt the boot sector is different.

EDIT: Actually, I guess I followed an older version of the instructions, since the date of that post seems to be newer than the last time I patched DOS 5.