IBM PS2 Model 70 Technical Reference (October 1990)
The IBM Personal System/2 Model 70 Technical Reference is IBM's 96-page model-specific interface reference for the PS/2 Model 70 (8570), Fourth Edition, October 1990. It covers four system boards, all with model byte F8 (Figure 1-1): Type 1 (submodel 09, 16 MHz 80386), Type 2 (04, 20 MHz 80386), Type 3 (0D, 25 MHz 80386) and Type 4 (1B, 25 MHz 80486). Vertical bars mark changes; the May 1988 first edition, which covers only Types 1 and 2, is also hosted.
Contents
From the contents page (p. vii):
- Section 1, System Overview (p. 1-1): description and model bytes, system board features (p. 1-4), I/O address map (p. 1-8), specifications (p. 1-9) including physical specifications (Figure 1-10), and a power supply section (pp. 1-15 to 1-16).
- Section 2, Programmable Option Select (p. 2-1): POS address map, card selected feedback, system board enable/setup, POS register 2, POS register 3 for Types 1 and 2 and for Types 3 and 4, POS register 4 (Types 3 and 4), memory presence detect and adapter enable/setup.
- Section 3, System Board (p. 3-1): 80387, Micro Channel implementation, exception reporting and matched memory, central arbiter, diskette drive and fixed disk connectors (p. 3-9), ROM and RAM, system and non-system memory, memory caching (p. 3-16), error recovery, memory subsystem control, memory maps and connectors, and the real-time clock and CMOS RAM (p. 3-31).
What this manual does not contain
It is a programming and interface reference: no FRU numbers, removal procedures, symptom index, schematics or component values.
What it settles
From the power supply section (pp. 1-15 to 1-16):
- The system-board voltages are +5, +12 and −12 V; the drives receive +5 and +12 V.
- Maximum current is 300 mA for the auxiliary device and 275 mA for the keyboard, at +5 V (Figure 1-12).
- Channel connector load limits (Figure 1-13) differ between the 16-bit and 32-bit slots:
| 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 outputs track within 50 ms of each other at power-on.
The physical specifications (Figure 1-10) give 360 × 420 × 140 mm, 9.55 kg, heat output 215 W (735 BTU/hour), automatic range selection between 90-137 V and 180-265 V, and 0.13-0.36 kVA input. The May 1988 edition gives 220 W.
Pages that cite this document
- IBM PS/2 Model 70 cites it.
- IBM PS2 Model 70 Technical Reference (May 1988) and IBM PS2 Model 70 Hardware Maintenance Reference list it as related.