8580 Type 3 Planar
25 MHz, -Axx Models

rf7080a.exe Model 70/80 Reference Disk v1.12 (zipped image)

190-055 IBM Personal System/2 Model 80 (8580-A21, -A31)
190-177 IBM Personal System/2 Model 80 (8580-081, 161 AND A16)
PS/2 Model 80 Technical Reference 3d Ed, Oct 1990

Planar Memory
Power Supply

Specifications
Type 3 Planar
System Firmware
   ROM Images
Axx Origins
8580 Memory Parity Errors ECA 051


Specifications

25MHz 8580-A16,A21,A31
386DX-25, socket for 387DX-25, 64KB of L2 cache.
DMA support on parallel port


Type 3 Planar 25 MHz (-A16, A21, A31) FRU P/N 85F0046 [P] [P]

F1 fuse solder pads
F2 1A fuse
F3 1.5A fuse
F4 2.0A fuse
J1 HDD-15 Video connector
J2 DB25 Serial port
J3 Parallel port
J4 Mouse port
J5 Keyboard port
J6,7 16-bit MCA slot w/ AVE
J8,9 Memory expansion connectors
J10-13 32-bit MCA slot w/ MME
J14,15 16-bit MCA slot
J16 Power supply connector
J17 Solder pads for two pin header
J18 Floppy connector
J19 Battery/Speaker connector
U3 Inmos IMSG171P-35 RAMDAC
U7 23F3001
U14 LM340T5 7805 5V reg. (incl. SCP)
U15,17,22,23,26,30-32
   M5M4464AL-12 64Kx4 DRAM (video)
U16 90X8941 VGA
U42 57X4111 MS700CD
U48 NS16550AFV UART
U54 82385-25 Cache controller
U59 P8042AH Keyboard controller
U96 80386DX-25
U99-106 M5M5178P-33 8Kx8 SRAM
U120,121 N8259A-2 PIC (cascade)
U131 NEC µPD72065L Floppy controller
U132 Motorola MC146818AFN RTC/CMOS
U137 72X8299 PIO
U140 67F4356 BIOS Even
U141 67F4355 BIOS Odd
U147 90X8134 DMA
U152 Sanyo LC3664NML-12 8Kx8 SRAM
U165 387DX Math co-pro socket
U175 LM386 Audio Op-Amp (PC Speaker)
Y1 28.322 MHz osc
Y2 25.175 MHz osc
Y3 1.8432 MHz osc
Y4 50.0000 MHz osc
Y5 32.0000 MHz osc
Y6 32.8 kHz xtal (RTC)
Y7 14.318 MHz osc
Y8 40.0000 MHz osc

The -Axx supports up to 8MB on the planar, using 4MB System Memory Boards.
The Model 80 A21 and A31 parallel ports support Direct Memory Access (DMA) parallel communications.

Four 32-bit slots with Matched Memory Extension (MME), and four 16-bit slots (two with AVE, one occupied with 16-bit SCSI controller).


System Firmware (POST & BIOS)

Firmware stored in EPROM.

ROM Images

64F3084 / 64F3085 - 21 Nov 1989, rev. 1, 2x 27C512-1JL (U140 / U141)
64F4356 / 64F4355 - 15 Feb 1990, rev. 2, 2x 27C512-1JL (U140 / U141)


8580-Axx Origins (from Major Tom)

The 8580-Axx planar looks very Japanese. Just look at the silkscreen - all components have an outline around/under them, most components use the odd (but helpful) ID/type scheme, and there's also a dedicated space for the EC # sticker. All typical signs for boards designed by IBM Japan.

It doesn't quite explain the socketed K/B controller, because even if that was something that IBM Japan liked to do, IBM (US) could simply drop the socket for boards manufactured in the US. Unless all Axx boards were actually manufactured in Japan as well...

The two AVE slots (again, a feature exclusive to the 80-Axx board) would also make more sense in this context. Most, if not all, PS/55 machines were equipped with one of the special Japanese Display Adapters that were necessary to display proper Kanji characters. PS/55 Model 5570 was the Japanese equivalent of "our" PS/2 Model 80. The 5570-Vxx systems were equipped with the 25 MHz -Axx planar and the Display Adapter II card - an AVE adapter! Now, since having one of these cards was pretty much mandatory for the Japanese market, you would be left with no empty AVE slots - which would limit the expandability somewhat...

Ed. The older PS/55 5550 386 planars have two AVE slots as well, which pretty much confirms this theory.

Later, when the BVE extension was introduced to the MCA world, IBM Japan moved the DA board to that slot instead. This is known as the BVEC series. Unlike the older AVEC series, these later adapters have VGA onboard. So, in this iteration, they could get away with the more typical configuration of one BVE slot and one AVE slot.


8580 Memory Parity Errors ECA 051

M/T 8580 MODELS A21, A31 AND A16: INTERMITTENT OS/2 TRAP ERRORS

25MHz 8580 systems with 8MB of system board memory installed which are experiencing intermittent planar memory parity errors, such as OS/2 Trap 0002 or NMI errors on other complex operating systems.

Physical Check: Examine the modules in position "U24" and "U34" located near J8 and J9, the system board memory sockets. If the part number on the module is FCT841, the system board should be replaced using this ECA.

┌─── IMPORTANT PLEASE READ ──────────────────────────────────────────────┐
│ INFORMATION PRINTED ON THE SYSTEM BOARD NEAR THE MODULE SHOULD BE      │
│ IGNORED.  ONLY INFORMATION PRINTED ON THE MODULE SHOULD BE USED WHEN   │
│ MAKING THIS PHYSICAL CHECK.                                            │
└────────────────────────────────────────────────────────────────────────┘

Modules with any identification other than "FCT841" (such as F841, 841D, 72F841, 72F841D, etc.) are good and the system board does not qualify for this ECA.

Detail: Intermittent Trap 0002 errors may be experienced on 25MHz 8580 systems running OS/2 due to a timing condition on the system planar. Other complex operating systems may experience NMI or other errors depending upon the characteristics of the operating system.

Notes: This ECA only applies to the 25MHz 8580 models listed above which have the affected module numbers in position "U24" and "U34." Other 8580 models are not affected and are not eligible for this ECA.

Content created and/or collected by:
Louis Ohland, Peter Wendt, William Walsh, David Beem, Tatsuo Sunagawa, Jim Shorney, Tim Clarke, Kevin Bowling, Tomáš Slavotínek, and many others.

Ardent Tool of Capitalism - MAD Edition! is maintained by Tomáš Slavotínek.
Last update: 23 Oct 2021 - Changes & Credits | Legal Info & Contact