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, 3rd Ed. (Oct 1990)
Type 3 Planar
8580 Memory Parity Errors ECA 051
25 MHz 8580-A16, A21, A31
386DX-25, socket for 387DX-25, 64 KB of L2 cache.
DMA support on parallel port
Type 3 Planar 25 MHz (-A16, A21, A31), Japanese design - used in PS/55 Model 5570-Vxx
FRU P/N 34F0022, P/N 33F5571
FRU P/N 85F0046, P/N 91F7513
F1 Fuse solder pads
F2 1 A fuse
F3 1.5 A fuse
F4 2.0 A fuse
J1 HDD15 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
U14 LM340T5 7805 5V reg. (incl. SCP)
M5M4464AL-12 64Kx4 DRAM (video)
U16 90X8941 VGA
U42 57X4111 MS700CD
U48 NS16550AFV UART
U54 82385-25 Cache controller
U59 P8042AH Keyboard controller
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 Controller
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
The Model 80 A21 and A31 parallel ports support Direct Memory Access (DMA)
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.
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
25 MHz 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: 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
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 25 MHz 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