IBM PS2 Model 80 Technical Reference (October 1990)
The IBM Personal System/2 Model 80 Technical Reference is IBM's 96-page model-specific interface reference for the PS/2 Model 80 (8580), Third Edition, October 1990. It covers three system boards, all with model byte F8 (Figure 1-1, p. 1-3): Type 1 (submodel 00, 16 MHz), Type 2 (01, 20 MHz) and Type 3 (80, 25 MHz). The Type 3 board adds a 64 KB two-way set-associative store-through cache and has two system-board memory connectors. Vertical bars mark changes; the April 1987 and May 1988 editions are also hosted.
Contents
[edit | edit source]From the section contents pages:
- Section 1, System Overview (p. 1-1): description and model bytes, system board features, I/O address map (p. 1-6), specifications (p. 1-7), and a power supply section (pp. 1-12 to 1-14): outputs, output protection, voltage sequencing and power supply connectors.
- Section 2, Programmable Option Select (p. 2-1).
- Section 3, System Board (p. 3-1): 80387, Micro Channel implementation and exception reporting, the matched-memory extension with its signals and cycle timing, central arbiter and arbitration priorities, ROM for Type 1 and for Types 2 and 3, RAM, system and non-system memory, memory caching, and the rest of the memory subsystem, real-time clock and CMOS RAM and system ports.
What this manual does not contain
[edit | edit source]It is a programming and interface reference: no FRU numbers, removal procedures, symptom index, schematics or component values.
What it settles
[edit | edit source]The physical specifications (Figure 1-8) list three power supplies, 225 W, 242 W and 250 W, with heat outputs of 350, 375 and 390 W and maximum input of 0.58, 0.62 and 0.65 kVA respectively. The unit is 165 mm wide (318 mm with the feet extended), 483 mm deep and 597 mm high, and weighs 20.6 kg with one fixed disk drive; input range is selected automatically between 90-137 V and 180-265 V.
From the power supply section (pp. 1-12 to 1-14):
- The system-board voltages are +5, +12 and −12 V; the drives receive +5 and +12 V.
- Maximum currents (Figure 1-10): internal fixed disk drives 2.5 A at +12 V and 1.5 A at +5 V per supply connector; auxiliary device 300 mA and keyboard 275 mA at +5 V.
- Channel connector load limits (Figure 1-11):
| Supply | 16-bit connector | 32-bit connector |
|---|---|---|
| +5 V | 1.6 A | 2.0 A |
| +12 V | 0.175 A | 0.175 A |
| −12 V | 0.040 A | 0.040 A |
- A short on any output, or an internal overvoltage before any output exceeds 130 % of nominal, latches all outputs off until the fault is removed and the power switch has been off for at least ten seconds (the April 1987 edition says one second). The outputs track within 50 ms at power-on.
- The two 4-pin fixed disk connectors carry +12 V on pin 1, DC return on pins 2 and 3 and +5 V on pin 4 (Figure 1-12).
Pages that cite this document
[edit | edit source]- IBM PS/2 Model 80, IBM PS/2 Model 80 Maintenance Guide and IBM PS/2 Model 80 Troubleshooting Guide cite it.
- IBM PS2 Model 80 Technical Reference (April 1987), IBM PS2 Model 80 Technical Reference (May 1988), IBM PS2 Model 80 Schematics and IBM PS2 XGA Display Adapter A Technical Reference (September 1990) list it as related.
Download: IBM PS2 Model 80 Technical Reference Oct90.pdf
Related pages
[edit | edit source]- IBM PS2 225W Power Supply 72X6665 Schematic (Tube Time, 2024), a schematic of the 225 W supply