Apple III Plus Owner's Guide
The Apple /// Plus Owner's Guide (Apple Computer, Inc.) is Apple's own guide for the Apple III Plus. Read alongside the Apple III Owner's Guide it is the clearest statement of what actually changed between the two machines.
What is in it
[edit | edit source]- The clock/calendar battery. The III Plus clock/calendar "runs on three size AA battery cells", in a clip "located between the power supply and the speaker on the exterior front wall of the computer well, inside the Apple III's cover". Apple's own warning: "Some types of battery cells are more prone to leak than others. Periodically check your batteries for leakage. When installing or replacing batteries, be sure you do not use carbon-zinc cells."
- Appendix D, System Specifications - the same case and weight as the Apple III (17.5 × 18.2 × 4.8 in, 26 lb), 6502B at 2 MHz peak / 1.4 MHz average, minimum 128K of RAM, 4K of ROM for initialisation and diagnostics, a high-voltage switching supply at +5/−5/+12/−12 V 1 A, UL/CSA approved, 100 W maximum, and an ambient temperature range of 0 to 45 °C where the Apple III's guide gives 15 to 35 °C.
- 75 keys (62 on the main keyboard, 13 on the numeric pad) and five special keys - TAB, ESCAPE, RETURN, ENTER and DELETE - where the Apple III has 74 keys and four.
- The text interlace mode, 560 × 384 dots, which requires a green-phosphor monitor.
- Appendix B, port specifications: the RS-232-C DB-25 pinout, the separate DB-25 disk port carrying up to three daisy-chained Disk III drives, and the 15-pin colour video connector that "supplies seven different video signals and four power supply voltages".
- The security mount - an 0.25 inch unthreaded hole in the baseplate to the left of the internal speaker.
Download: Apple III Plus Owners Guide.pdf