THE IBM PORTABLE PERSONAL COMPUTER 5155 MODEL 68
Notes on my IBM Portable machine.

[pic/4s.jpg] [pic/4.jpg]SYSTEM INFORMATION
* IBM Compatible (100%, heh)
* 8808 at 4.77 MHz
* 640 KiB ram
* 2x 360 KiB 5.25 inch floppy disk drives

DOCS
IBM_5155_5160_Technical_Reference_6280089_MAR86.pdf
[docs/IBM_5155_5160_Technical_Reference_6280089_MAR86.pdf]
80X0945_DOS_3.30_Technical_Reference_Apr87.pdf
[docs/80X0945_DOS_3.30_Technical_Reference_Apr87.pdf]
DRIVERS / UTILS
TODO: Investigate what is out there.

CF CARD HARDDISK: SETTING UP XT CF LITE 4.1 (XTIDE UNIVERSIAL BIOS)
My unit has two floppy drives, and rather than changing that configuration for a
half height MFM drive (which I could have done), I chose to keep both drives in
the machine, and install a CF card harddisk emulator instead, this also allows
me to conveniently transfer files back and forth between the IBM and a modern
computer.

The card I bought was configured to: BIOS RAM address: 0xCA00 IDE controller
base address: 0x300 and Boot driver at 0x80. After inserting the card, the
machine booted and showed the XTIDE Universial BIOS as expected.

USING AN EMULATOR TO PREPARE AN IMAGE FOR THE CF CARD
I chose the easy way, since I don't have DOS 3.30 floppies, I found the images
online, and used PCem.
* Machine: [8088] IBM XT
* CPU: 8088/4.77
* Memory: 640 KiB
* Video device: VGA (Speed: default)
* Sound: None
* HDD: [IDE] XTIDE
* FD1: 5.25 360k
* Drive 0 Primary Master C: Type: harddrive
* No network card



With the virtual machine as close to original as I could manage, I went ahead
and used PCem to create a 64 MiB harddisk image (type: custom) and booted the
IBM PC-DOS floppies in the emulator. Then I installed DOS using the steps
described below.

INSTALLING IBM PC-DOS
These steps are the same whether you're installing DOS on PCem with floppy
images or on the IBM hardware with floppy disks. They also apply to real
harddisks, but you may need additional configuration of the HDD controller and
low-level formatting first.

Below is (more or less) a transcript of the installation after booting dos.


Checking ram...
XTIDE BIOS stuff...
Booting A..
Current date is Tue 1-01-1980
Enter new date (mm-dd-yy):
Current time is 0:04:15.56
Enter new time:

Microsoft(R) MS-DOS(R) Version 3.30
            (C)Copyright Microsoft Corp 1981-1987

A>fdisk

-----

Fixed Disk Setup Program Version 3.30
(C)Copyright Microsoft Corp. 1987

FDISK Options

Current Fixed Disk Drive: 1

Choose one of the following:

   1. Create DOS partition
   2. Change Active Partition
   3. Delete DOS partition
   4. Display Partition Information



Enter Choice: [1]


-----


Create DOS Partition

Current Fixed Disk Drive: 1


   1. Create Primary DOS partition
   2. Create Extended DOS partition




Enter choice: [1]


-----


Create Primary DOS Partition

Current Fixed Disk Drive: 1

Do you wish to use the maximum size
for a DOS partition and make the DOS
partition active (Y/N).........? [y]


-----

System will now restart...

System reboots...

-----

XTIDE BIOS stuff..

Booting C
Missing operating system..


At this point, the XTIDE card sees that there is a partition on the CF card and
wants to boot it, but it will fail. Press CTRL+ALT+DEL and press A when the
XTIDE BIOS info comes up (just press it a lot of times until it says "Booting A"
(note, on PCem, you also send CTRL+ALT+DEL from the menu).


----
XTIDE BIOS stuff..
Booting A...
Dos boot stuff...

A>format C: /s

press y...
wait for it to finish..

A>md C:\DOS

A>copy A:\ C:\DOS

list of files...
If you've got more DOS floppies, repeat... copy command for each. (there are two floppies for IBM PC-DOS 3.30

Then create a basic autoexec.bat with edlin:

A>C:
C>cd DOS
C>edlin C:\autoexec.bat
New file
*i
   1:*@echo off
   2:*prompt $p$g
   3:*path=C:\DOS
   4:* ((Here you press ctrl+c))
*E

C>


That's it! You're now ready to reset the machine/vm and boot DOS, it will have a
nice and familiar C:\> prompt.

screenshot of PC-DOS booted from XTIDE in PCem [pic/pcem-doss.png]
[pic/pcem-dos.png]FLASHING THE HARDDISK IMAGE ONTO THE CF CARD (LINUX)
[pic/6s.jpg] [pic/6.jpg]
My >CF->IDE->USB, power jury rigged from 9 volt battery. While waiting for my
CF->USB adapter...

Turn off PCem (shut down the virtual system), and the image is ready to flash
onto the CF card for use in the real machine (assuming you did the above in
PCem). The image is as raw as it gets, so you can just use DD.

First, insert your CF card in your card reader and plug it into a USB port. Now
check which device identifier it got with dmesg. Mine got /dev/sdd, yours will
get something else, BE CAREFUL! Doublecheck with fdisk (the linux one) and check
that the device has the expected capacity (that's a somewhat reliable indicator
in this one case) double-check by doing ls on the device, remove usb, confirm
file not found, re-insert, do ls again, and confirm file found. Just be careful,
ok..

sudo dd if=/path/to/your/pcem-image.bin of=/dev/that-cf-card-device

Note, the cf card may already be partitioned, it would appear for example as
/dev/sdd and /dev/sdd1, you should provide the device itself ( /dev/sdd for
example) and not the partition (which would be /dev/sdd1).

After the image is copied, re-plug the CF card and it can be mounted and
additional programs transferred before moving it to the real machine. That's
it.. you're ready to move it to the real machine and do some delicious portable
computing!

MORE PICTURES
picture of ibm portable xt [pic/5s.jpg] [pic/5.jpg] picture of ibm portable xt
[pic/3s.jpg] [pic/3.jpg] picture of ibm portable xt [pic/1s.jpg] [pic/1.jpg]
picture of ibm portable xt [pic/2s.jpg] [pic/2.jpg]
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Last edited: 2020-08-25 - No need for a disclaimer, I've done nothing wrong!

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