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Model 5560

Model 5560-N Brochure (-N0B/NYB/NMB/NMY) RICOH PS Model 5560 Brochure (-W28/W2B) Power Supply PS/55 Processor Complexes General Information 5560 Planar System Firmware J25 Remote Power-ON Request J28 Front Panel Connector J31 Op Panel Connector Model Types    5560-W    5560-N Memory Video SCSI Adapters Inner View

Model 5560-N w/ CADAM keypad

Content created by Sandy and Major Tom.

General Information

5560-W was the first desktop model with 486 class CPU. It was introduced to the market on Oct. 1990 together with 5580-Y.

5560 is based on PS/2 Model 90 (8590/9590). It uses a similar, but not identical chassis. The planar has been redesigned, and so were some of the processor boards. The main differences are:

• No memory risers, SIMM sockets are directly on the planar (photo)
• Two extra 32-bit MCA slots in place of the memory riser connectors (2/3 length) (photo)
• No XGA video on the planar
• The second serial port is missing
• Power connectors are not card-edge type (more info, photo)
• The PSU can be swung out, similar to Model 95 (and even operated in that position) (photo)
• PC Speaker volume pot on the front panel (front panel, chassis)
• Provision for Op Panel (diagnostic LED display), not populated
  (planar I/O, chassis stripped, chassis populated, LED display mockup, removable cover)
• More convenient SCSI adapter location, better cable routing, standard 50-pin header
• Other minor changes (cover slide bracket, cover lock, modified slot covers)

Photos: front, front #2, back, back PSU, short slot, inside, inside #2, -W1B w/ "kit W2B"

5560 Series Lineup (-W/N, original HERE)

5560 Planar FRU P/N 79F2592, P/N 79F0084 or 79F5496

J7 pre-installed Japanese Display Adapter B-II or XGA-2
J12 pre-installed 2/3-length SCSI adapter

Important: The original electrolytic SMD capacitors are prone to leaking! If your board is affected by this problem, you should replace the capacitors and clean the board as soon as possible. Otherwise, the leaking electrolyte will inevitably destroy the board!
All 21 SMD capacitors are of the same type - 33 µF 25 V (d = 6.3 mm).
It's safe to use 16 V parts. Polymer or tantalum capacitors can be used as an alternative.

Important: The SIMM sockets on the planar are not angled, which limits the SIMM height to approximately 28 mm. Most IBM modules are ~25 mm tall, which leaves only some 3 mm of clearance between the top edge of the module and the PSU. Make sure the used modules are not too tall before you swing the PSU over the planar!

System Firmware (POST & BIOS)

Firmware stored on the Processor Complex.

J25 Remote Power-ON Request (not populated)

The unpopulated header J25 can be used to turn the system on (and off) from an external source. This can be achieved by connecting pin 2 to ground (either of the remaining pins). For this to work the Op Panel must be also installed.

Pin 2 is directly connected to pin 33 of the nearby Op Panel connector (J31, also unpopulated) and pin 8? of the Front Panel connector (J28).

J28 Front Panel Connector

Looking at the plug (female) from the front:

Note: The pin numbering is made up. The PCB has the pins marked incorrectly on the silkscreen (duplicate numbers).

The volume pot is 10 KΩ (linear?) with a middle position detent.

J31 Op Panel Connector (not populated)

Provides similar functionality as the Model 95 Op Panel header, the pinout is different however. It was likely to be used together with the Front Panel header (J28) but only with a smaller (2x8-pin) connector populated (J28 and J31 partially overlap - both physically and functionally).

Note: Additional components must be populated for the Op Panel to function. At the very least U58 (74ALS245) and possibly some other.

Processor Complexes

60-W0x Complex (486DX 25 MHz)
60-W1x/W2x Complex (486SX 25 MHz / 486DX2 50 MHz)
N / DX2-66 Upgrade Type-B Complex (486DX2 66 MHz)

Model Types

As described HERE there are 4 types of 5560:

• 5561-W0x - 486DX-25: If you have filled all SIMM sockets with 8 MB SIMMs, you'll have enough time for cigarettes and a cup of coffee (or two) until the machine finishes the memory count.
• 5561-W1x - 486SX-25: Faster memory count than -W0x.
• 5561-W2x - 486DX2-50: Most likely the same complex as in -W1x.
• 5561-Nxx - 486DX2-66: Supercharged 5560 with a Type-B DX2-66 upgrade platform.

5560-W

5560-N

Model 5560-N Brochure

*1 NYB : OS/2 model
*2 NMB : MCADAM/2 (CAD software) included. ASYNC TTL /Adapter is included.
*3 NMY : MCADAM/2 upgrade version. ASYNC TTL/Adapter is included.

Memory

8 x 72-pin SIMM sockets mounted directly on the planar.
Parity 8 MB/70 ns SIMMs are mandatory for -W1, -W2 and -N complex.
For W0 complex, 80 ns SIMMs are standard, and must be used in matched pair.
For W0/W1 models, reference ver. 1.11 is required to use more than 16 MB of RAM.

Video

No video on the planar.
32-bit BVE slot with PS/55 Display Adapter B-2 or XGA-2 installed.
32-bit AVE slot available.

SCSI Adapters

A 2/3-length 32-bit uncached SCSI /A adapter P/N 79F1140 was used for model -W0. The adapter has both the standard 50-pin header and the IBM card edge connector.

A stock SCSI adapter for the -W1/W2 models is a 2/3-length 32-bit SCSI/A w/ cache and a standard 50-pin header, P/N 95F4488. It uses the usual @8eff (32-bit with cache) ADF. SCSI microcode set is 64F4376/64F4377.

Model 5560-N was equipped with a short SCSI Adapter II/A (32-bit) with 512 KB cache (marked as 06G6760 in sales leaflets, and I think it's either 35G2818 or 07G3063).

Inner View

Photos below are inner view of my 5561-W1B with Type-B Upgrade processor complex installed. Half-sized cached SCSI A/32 with 50-pin header was replaced with a short caching SCSI 32/A with new microcode set.

You can see an AMD 5x86-133 CPU on an interposer with a low-profile heatsink. The CPU runs at 160 MHz (internal). No CPU fan, but the front fan blows a fresh air over the heatsink.

Picture #1 - Adapters (top to bottom)
	#6: Madge Smart Ringnode MC32 #5: XGA2 #4: ACPA #3: Intel Fax/Modem Adapter Complex: DX2/66 Upgrade Type-B    w/ interposer - closeup 1, closeup 2 #2: (empty) #1: Short Cached SCSI (w/ new microcode)
Picture #2 - SIMMs and Power Connectors
	You can pull the PSU forward and then swing it to right side, similar to Model 95. Notice how different the power connections are when compared to Model 90. Tall SIMMs are not good for 5560. There isn't much space between the SIMM slots and the PSU (~28 mm).

Sandy's 5561-W1x (upgraded with 60-N complex)

64 MB of RAM, BIOS modified N complex with 80 MHz osc, AMD 5x86 running x4 speed, ATI-GUP, Madge Ringnode MC32, Genuine IBM SCSI A/32 with cache, 650 MB + 1 GB hard drive, Hitachi 2x CD-ROM without bezel.