Ardent Tool of Capitalism

Model 5545

3070V150.zip Reference & Diagnostic Disk for 5530-5570-S,T,V & possibly 5545-T v1.50 (DOS/V)
   3070V150R.zip Reference Disk for 5530-5570-S,T,V & possibly 5545-T v1.50 (DOS/V)
   3070V150D.zip Diagnostic Disk for 5530-5570-S,T,V & possibly 5545-T v1.50 (DOS/V)
3070V136.zip Reference & Diagnostic Disk for 5530/5540/5545/5550/5570 v1.36 (JDOS)
5545r133.exe Ref for 5545 (P-70/386 JP version) v1.33 (JDOS) [P/N 65F0046]
5545UTL.EXE Utility Diskette for 5545 v1.00 [P/N 64F8330]

IBM Japan's OS/2 Portable (BYTE, Oct 1990; English; archive.org)
IBM PS/55 5545 Advertisement (Super ASCII VOL.1 #1, Aug 1990; Japanese; archive.org)

PS/55 5545 and PS/2 P70 Planar Comparison

Introduction 5545 and 8573 Models Reference Disk 5545 Planar CPU Memory MCA Riser Display Adapter Plasma Display Power Supply Unit Hard Disk 5545 Case Keyboard

PS/55 5545-T

Content by Tatsuo "Sandy" Sunagawa and Tomáš "Major Tom" Slavotínek.

Introduction

The 5545-T, released in May 1990, is the PS/55 version of the PS/2 Model P70 (8573). One may think that it was the P70 from IBM (USA) rearranged by IBM Japan (like with the 8580/5570), but in fact that does not appear to be the case. This machine was apparently developed by IBM Japan's Yamato Laboratory, with the 5545-T for the Japanese market and the 8573 P70 for the worldwide PS/2 market.

Its outward appearance resembles a briefcase. Its most notable features are the orange gas-plasma display and the keyboard that doubles as the machine's lid. It comes with a 386DX-20 CPU, an ESDI hard disk, two MCA slots (one of which is for a half-size card), and it is equipped with one parallel output, one serial output, a mouse port, and a connector for an external display.

As for the PS/2 branch, a successor machine called the P75 was released later. It adopted a 486DX-33, had a built-in SCSI interface, and used an XGA display — quite high specs for the time. But unfortunately, there was no equivalent P75 model released in Japan under the PS/55 branding. By that time, ThinkPad was already the mainstream portable PC in the Japanese market, so presumably IBM Japan determined that a form factor like the P7x would not match market expectations. Because it was developed by IBM Japan, I imagine that the P75 may have circulated among foreign-based companies, but even the 5545-T is rather rare, and the P75 is likely impossible to find within Japan.

The form in which the front cover doubles as the keyboard is similar to Fujitsu word processor OASYS devices, and a similar design was used by other machines like the Compaq Portable. The plasma unit can be tilted — this is the same in the OASYS as well — and its mechanism is quite well designed. Also, the FDD unit located on the right side has a rather interesting mechanism in which its top portion slides forward. Although it is described as portable, it is quite large and heavy, so it is more like a space-saving desktop. The keyboard that doubles as a lid adopts ALPS switches similar to those of the 5576-002, and its key layout is also that of the -002 type. With the PS/2 P7x series, the usual 101 layout is used, so if one wishes, one could modify the cable to use it with a modern PC; however, the 5545-T keyboard uses the -002 layout, so a little extra work is needed to use it with Windows 2000 or XP.

Since the P70 is introduced as VGA, it appears that the 5545-T, which has high-resolution PS-55 display capability, differs in that aspect. Additionally, the motherboard also shows differences.

For more information about Sandy's 5545-T and its revival — see HERE (Japanese).

5545 and 8573 Models

Reference Disk

A common Ver.1.50 (DOS/V version) for 386-based 5550 machines can be used.

Sandy had a diskette called "5545-T ver3." on hand, but for some reason, his machine rejected it. At the time, he was working under conditions with no screen output, so he could not investigate further.

5545 Planar

"SYS CARD J" (Japanese design, manufactured by Matsushita)

20 MHz: "IGH 0396BA", FRU P/N 65F0064, P/N 65F0028 (photos by Daehan Lee; xtal removed)

This board is similar to the "New" P70 Planar, with the following notable differences:

I/O GA 65X1380 instead of 33F5838
8042 38F7099 populated instead of solder pads
ROM 79F7128 instead of 56F7439
Y4 40.0000 MHz instead of 32.0000 MHz oscillator
Ext FDD connector and related circuitry are missing (not even pads are present)

There are many other minor differences between the two boards. For a more detailed comparison see HERE.

CPU

Only the -T model with a 386DX-20 CPU was released. An 80387 was provided as an option.

Evergreen 386DX3+ (IBM486BL3) upgrade might be possible. Another possibility is a TI upgrade CPU.

Memory

It requires an 85 ns IBM-proprietary SIMMs. The motherboard has four slots, for a total of 8 MB. According to the PC Guide Book published by IBM Japan, the maximum memory capacity is 16 MB, but this almost certainly refers to the total capacity when using the 2-8MB memory expansion adapter.

MCA Riser

"iGH0256DA", FRU P/N 56F9101, P/N 56F9047, PCB P/N 65X1308 | (photos by Daehan Lee)

CN1 32-bit MCA slot w/ MME
CN2 16-bit MCA slot

Identical to the 8573 P70 riser.

Display Adapter

FRU P/N 65F0052, C/A P/N 79F1138 | | (photos by Daehan Lee; fuse removed)

Custom logic implemented using Toshiba TC110G CMOS gate arrays. The general architecture is the same as with other Japanese Display Adapters, but the gate arrays appear to be a different revision.

The 5545 uses PS/55 Japanese Display Adapter, meaning high-resolution display is possible.

Sandy's 5545-T displayed extremely tiny characters under (English?) DOS. It may be possible to mitigate this by modifying the DOSV INI.

Display Adapter Daughter Card

FRU P/N 65F0053, C/A P/N 79F1139 (photos by Daehan Lee)

J1 100-pin connector U1,2,5,6 TC511665J-80 64Kx16 DRAM U3 79F1359 PG2 TC110G38AF U4 79F1357 PV4 TC110G38CG

Plasma Display

Matsushita Electric MD768L1066PG1, IBM P/N 64F8791 (photos by Daehan Lee)

The panel resolution should be either 1024x768 or 1040x725 pixels — much higher compared to the P70's 640x480 resolution. Verification needed.

Power Supply Unit

P/N 65F0032
FRU 65F0055
100-240 V~
2.6 A
1 Φ (Single Phase)
50-60 Hz
0.25 kVA

Maximum Power Consumption: 154 W
During normal operation: ? W

Hard Disk

The machine uses a DBA-ESDI hard disk, typical for the 386 era. The upper limit of available drives is around 160 MB.

By using the Data Card MC32, you can add memory and simultaneously use a 2.5-inch IDE hard disk. But since there is only one full-size slot, it's a dilemma.

Another option is to use a a Japan-specific SCSI/A P/N 35G3785, which mounts a 2.5" SCSI HD on the board. However, high-capacity 2.5" SCSI HDs are nearly unobtainable.

5545 Case

FRU P/N 64F8373, P/N 64F8375, IPB0075
Mitsubishi Rayon FC-30, Tohoku Munekata C1084

At first glance, the 5545 case may appear identical to the P70, but there are several key differences:

• The floppy drive mounting mechanism is different
• The plasma display is mounted differently and the cable openings are different too
• Further, the plasma display power cable is routed differently.
  Instead of going around the planar like on the P70
  it goes behind it in a shallow vertical channel.
  
• The case has different assembly and mould part numbers compared to the P70
• The badge and model stickers are different too, as one would expect

Back Cover

FRU P/N 78F9923, P/N 78F9877, IPB0076(XX)
Mitsubishi Rayon FC-30, Sankyo Kobunshi A1027-A, Ikegami Kaken Kogyo IKK-9

The back cover also has some differences:

• Since the 5545 lacks an external floppy connector, the I/O area of the cover is different
• The cover has different assembly and mould part numbers compared to the P70
  Also note the different metal paint on the inside of the cover.

All case photos provided by Daehan Lee.

Keyboard

Along with the gas plasma display, the keyboard is one of the 5545's defining features.

The keyboard for the P7x is introduced on this page by Mr. pingjingbo (archived). The 5545 keyboard is similar but uses the 5576-002 layout, which was IBM Japan's main keyboard layout at that time (the positions of the Alt and Ctrl keys differ from the later A01 layout).

Like the -002, it uses an ALPS leaf spring switches, and its feel and keystroke sensation are very similar. It uses single-piece keycaps, which differs from the 5575-002. Also, there is no steel plate like the on the -002, so the keystroke feel is somewhat diminished. Because this PC was marketed as a luggable, they probably had no choice but to omit a steel back plate in order to reduce weight.

From a distance, the connector/plug combo on the keyboard side looks somewhat like those of a PS/55, but in reality they're quite different. The plug/connector is made by HIROSE.

For details on the keyboard itself, please see this page.