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Re: XT-IDE on PCjr
Posted: Tue Oct 16, 2012 9:12 am
by Tempest
I've been gone for a while. I hope I'm not to late to get in on this.
Re: XT-IDE on PCjr
Posted: Tue Oct 16, 2012 10:00 am
by alanh
I just sent you a PM. There are plenty of boards left.
Re: XT-IDE on PCjr
Posted: Tue Oct 16, 2012 3:03 pm
by jltursan
Hargle wrote:
There was one other snafu:
I have a DOS 5.0 disk, with the PCjr patch applied to the boot sector. I boot to this disk, fdisk the DOM and then format /s it. The DOM would not boot. I could see it blip 1 time on the LEDs and then hang. Next thing I did was fdisk /MBR the drive, and after attempting to reboot again, I saw it blip 3-4 times on the LED and then drop me into BASIC. It turns out that I had to apply the same patch to my boot sector (located on cylinder 0, side 1, sector 1) before the machine would boot to it. that stumped me for a bit, as I thought that we only had to be done to the floppy disk you use to first boot to, not the HDD too.
Anyway it appears kingspec DOMs work great. I have a spare 44pin one if you'd like it.
They also have Micron flash on 'em, so they have to be good.
Yep, I stumbled with the same problem
here, while trying to install IBM-DOS 5.0 in a 64MB CF card

. It finally worked great!
Thanks for the feedback of DOM disks, it has helped me to convince myself to purchase this
one 
. I'll check it as soon as it arrives.
Re: XT-IDE on PCjr
Posted: Wed Oct 17, 2012 5:32 pm
by Hargle
ahhhrgh!
I just discovered that the 44pin DOM that I have is about 1/8" too wide and it overlaps one of the mounting holes enough that I can't put it inside a shell. I think my only course of action is to dremel the inside of the shell slightly so that the taller plastic standoff is removed. total bummer. luckily the pin for mounting it in the sidecar easily passes by the edge of the card, but the inside plastic part is too wide. luckily it's all internal so once the thing is buttoned up no one will know.
Re: XT-IDE on PCjr
Posted: Thu Oct 18, 2012 1:45 pm
by jltursan
Can't you extend the jrIDE IDE connector using a short cable enough to free the hole?
Re: XT-IDE on PCjr
Posted: Fri Oct 19, 2012 12:08 pm
by Hargle
possibly, but the DOM is a female connector, 44pin and the header is male 44pin. I'd need to get some kind of weird and short 44pin extension cable to pull that off.
It took me almost 20 seconds to dremel off a corner of the internal plastic standoff inside the shell. i'm perhaps a bit impatient.

Re: XT-IDE on PCjr
Posted: Fri Oct 19, 2012 3:18 pm
by Brutman
Hargle wrote:possibly, but the DOM is a female connector, 44pin and the header is male 44pin. I'd need to get some kind of weird and short 44pin extension cable to pull that off.
It took me almost 20 seconds to dremel off a corner of the internal plastic standoff inside the shell. i'm perhaps a bit impatient.

I constructed such a cable for a different project, but they do exist:
http://ep.yimg.com/ca/I/cablesonline_2225_10522787
And yes, I too had to use a Dremel too to modify the sidecar shell lightly just to fit my IDE cable. (This is on the original prototype card - I did not use the right angle IDE connector but I should have.
Mike
Re: XT-IDE on PCjr
Posted: Fri Oct 26, 2012 4:15 pm
by Tempest
Ok I just got my jrIDE, but I want to make sure I'm hooking it up right. I assume the IDE cable goes on the connector on the end (it's the only logical choice), but does the red strip go up or down? Also, is there any special software I need to use this or will it automatically detect my hard drive (assuming it's a supported model)? I didn't see any instructions anywhere.
Re: XT-IDE on PCjr
Posted: Fri Oct 26, 2012 5:42 pm
by Brutman
If you look at this picture you can see the orientation of the cable:
The bottom right pin is pin one, marked with a square instead of a circle. That is where the stripe on the wire should wind up.
- Make sure that everything is powered off.
- If you are using a real hard drive (spinning rust) you should be using an external power supply. That should be off too. (I'm paranoid.)
- Make your connections. Double check the orientation of the cables.
- On startup the Jr will count to 640. Then the BIOS on the jrIDE will take over. It will attempt to detect your installed devices. It should identify your hard drive. If the hard drive does not support LBA addressing it will complain about it. (Many Western Digital drives smaller than 8GB are not supported because of this.)
- You still need to boot DOS from a floppy, run fdisk to partition, format the new partition, etc. And if you are using DOS 5 you need to patch the boot sector of the hard drive, just like you patched the boot sector of the floppy.
Mike
Re: XT-IDE on PCjr
Posted: Fri Oct 26, 2012 6:03 pm
by Tempest
Yep I got that far. I have a 3G Maxtor HD that it seems to recognize (it shows up in the boot menu anyway). Now I need to find a way to format it. I have some DOS 4 disks, but I think they might be going bad or something because when I try to tun the FDISK command from the Install disk I get a bad sector error. Somehow I need to find 5.25" disk images for DOS 3.3 and 5.0 (if I want a larger partition). I found .img files of them, but now I need to extract the files in an emulator and write them to a 5.25 floppy. Hopefully then I can get FDISK to work. I'm pretty close, I can feel it.