Mike's PCjr Page

Ok I think I have the Chicken or Egg theme...

I have the JR-IDE with a Maxtor 8.4G and it seems to be ok...BUT:
the drive has a large non-dos partition that DOS4 FDISK does not allow to be 'removed'
DOS versions after 4.01, FDISK does have the OPTION to remove a non-dos partition.
Ok....Now......I have DOS5 on 3.5" but can't boot from the 3.5"

FDISK for DOS5 is supposed to have the option to delete the non-dos partion.
But I can't copy DOS5 onto a 5.25 and make it bootable if I initially booted the JR with DOS4.01. ( is this the Egg ? ) hmmmm
then I'd have to patch it to boot.

anyway I need to get rid of the non-dos partition on the hard drive and format it properly.

I've looked for a program like Norton or DISKPART or DELPART but it seems the later will only work on windows machines..

there should be a LOW level format program for DOS that can get me to usable hard drive.
No I don't have another machine, I have a Win98 but could never get the 5.25 Floppy drive to work.....

anyway for those of you that have had these last 30 yrs with the jr to figure this out......what the heck is the solution.
Must be a simple dos program somewhere that can fix this..

Chuck

Wiping out a boot sector using debug.com:

f 9000:0 200 0
a
mov dx, 9000
mov es, dx
xor bx, bx
mov cx, 0001
mov dx, 0080
mov ax, 0301
int 13
int 20

Change 0x0080 to 0x0081 for the second hard drive.

As usual, thanks Mike..

I did just find a Maxtor Dos low level format program.
but I want to try your debug also on a Seagate that I believe may work with the Jr_IDE.

I'll report back with the results to possible add to the JR-IDE list of drives..

chuck

UPDATE;

the Maxtor 90840D4 cleaned up nicely, was able to FDISK and show 3.9G of active DOS space.
if I can get it formated, this drive may qualify for the good list.

I tried to use FORMAT C: /s

the response was to Insert a diskett in drive A: and press ENTER, not what I expected.

So now I defer back to the Jr-IDE experts.

I would have thought the system would see drive C: as it did when it booted up and the JR-IDE bios reported it as attached fine.

Just a note:
JRCONFIG is /v32
I do have Palmzip.sys installesd on LPT1: with the /F option

Should the HD now behave as a normal Drive or have I missed a step or config issue?

Update:

FDISK the harddrive into 3 parts, each 1Gb C: D: E:

was able to format each drive drive. FORMAT C: ( did not use the /S option)

wanted to copy the system files and this is where it got sticky.

SYS C: did not work, it was like it could not find the IBMDOSCOM, IBMBIO.COM, files.
kept asking to insert system disk in A:, and this had the boot disk in the drive...

did a quick chkdsk /v and the files were on the list as expected.
so I am not sure why the system files would appear to be missing when executing the SYS command..

Update: Working..

Got the Jr-IDE working with a Maxtor 90840D6 Drive 8.4GB
Here is a list of steps I took:

- Did low level format on HDrive per Mikes Debug instructions.
- Fdisk : made one active DOS partiton and kept it to no more than 2G ( larger produced a format Divide Zero Error )
- Formated the HD FORMAT C: /B used the /B because I read to use SYS it should be used. Also No Label
- Copied the system files over to the HD using Drive B:Sys C: I was having trouble with A: SYS C:
- Copy the COMMAND.COM TO C:

Now I moved all the other start up files config.sys, autoexec.bat that I used on the A: boot disk
I also added the Driver=Share.exe in my config.sys

Turned off the system and powered back up, hit ESC the chose boot option ‘C’

system started up fine.

Loaded Liesure Suit Larry on the HD and started the game, This system has the Tandy Mod. Game played fine.

So this was a good exercise and refresh for DOS after so any years.

Thanks to Alan and Mike, the addition of the Hard Drive to the Peanut is super..

As I mentioned I have a couple DOMs coming and will try them and report back.

thanks to all for the help.
Chuck_

Just wanted to share the end of this trip with upgrading to DOS5

- Set up the JR with two Panasonic Ju-256A227 3.5" drives A: and B:
- Had a fresh in box copy of IBMDOS 5.0 ( disk #2 had errors ugh )
- Made a copy of the good Disk 1 and used Mikes patch to make it bootable (thanks to Mike and Jim)
- ** side note since I booted with DOS4, I also had to use Debug For DOS4 to make the DOS5 disk bootable
learned this the hard way reboot... as the first thing you may want to do is use the DEBUG.COM on the new DOS5disk
does not work.....
- Also I had tried the PATCHA.BAT that is available, but it seemed to have issues, did not investigate as Mikes solution
doing it with DEBUG by hand worked, I wanted to move forward.
- Updated he CONFIG.SYS with stacks=0,0 and included jrconfig, palmsys and other items.
- Also I had mentioned to Mike that ANSI.SYS did not seem to work, well for the noobies or us old guys that don't remember our DOS years, the Original disks have 'compressed' files NAME.CO_ you cannot just rename these. ugh
this was a nice exercise in 'read the STARTUP DOS PAGES' luckily I had a set of DOS5 disks uncompressed with the files I needed since my set had Disk#2 errors and could not be extracted.
- Tested the new boot disk and it worked ...wow only took me 3 days.... not bad...
- Immediately made a DISKCOPY for backup, also again DISKCOPY had to be DOS4 since I had booted using that version for development.
- Next was to tackle the Hard disk using Alans JR-IDE solution and I have the Hyperdisk 512MB DOM, it was also as simple as using the SYS command (after you booted using DOS 5) ,
it took a little while to establish the system on the DOM, actually about 5 minutes or more, but when finished, all I had to do was to PATCH the DOM same as above, dont forget this is C drive so the load command is L 0 2 0 1 (2 for C drive)
same when done and you will write it back W 0 2 0 1

- Did CTRL ALT DEL, and hold your breath,,, wow it worked,,,,

So a few personal comments:

Need to thank Mike, Alan(JR-IDE), and Jim (trixter) for the patience they show to us members that endlessly ask
the same question they have no doubt, heard many many times, and still they make the effort to share 'in detail' their knowledge and experience. The Jr is a true luv of labor, while you can play Kings Quest, AlleyCat, Leisure Suit Larry and many others, word processing is always a trek back to the 80's, impact Okidata printer, Zip Cartridges and the story goes on and on. I know for me, this is more of a nostaglic trip as with most I am sure, that drives the energy to spend untold hours booting and watching a PCJR monitor glow.

Thanks to all of the JR folks that keep this peanut going. it is Fun !

chuck

I recently went through the process of patching IBM DOS 5.02 again. Remember, there are two things that need to be patched; the boot sector of the media (floppy or hard disk) that you want to boot from, and format.com. Format.com needs to be patched because it's carrying a copy of a boot sector in it.

Which also implies that once you patch format.com, it always makes PCjr bootable DOS diskettes. Which is not so good if you share the diskettes with other systems.

I've gotten into the habit of keeping two versions of format.com around; the original and the patched version for PCjrs, which I call formatjr.com.

Ok I did not know about patching FORMAT, how is that done?

It's basically the same process as patching the boot record. I don't know if the patch programs/batch files try to do it (or do it correctly.)

I'm pretty sure there is an earlier thread here that is very complete. Here is a quick recap.

The boot sector patch adds some extra code to copy the true amount of memory detected by the BIOS and copy it to the memory location where DOS is told how much memory is available. On a PC the location DOS is reading would be the same as the true amount of memory detected by the BIOS, but on a PCjr we have the "what to tell DOS number" and the true number. DOS never looks at the true number, thus the need for the patch. The extra code is basically a memory copy instruction from one location to the other. That's it.

The format.com patch is pretty much the same, except the offsets are different because the boot sector is in the executable. So you have to do a little work to find the embedded boot sector and then be careful doing the math for the offsets.