File:Apple-1 Operation Manual 1976.pdf

Apple Computer Company, Apple-1 Operation Manual, 1976. 15 pages. Apple's only manual for the Apple I, issued from 770 Welch Road, Palo Alto.

Contents: a one-page Specifications sheet; Section I Getting Started (keyboard and display connection, AC power sources, the four-step test program); Section II Using the System Monitor with the complete commented assembly listing of the 256-byte monitor PROM at $FF00–$FFFF; Section III How to Expand the Apple System (the 44-pin edge connector, DMA, refresh timing, PIA register map, single-step and slow-ROM circuits); and the schematic set, drawing 00101, sheets 1–3 of 3.

Figures this document settles for the Apple I:

• Microprocessor clock 1.023 MHz; effective cycle frequency 0.960 MHz,

 because four of every 65 clock cycles are taken by DRAM refresh.

• Video: composite positive video, 75 Ω, level adjustable between 0 and +5 V p-p;

 line rate 15,734 Hz; frame rate 60.05 Hz; 40 characters × 24 lines with
 automatic scrolling; 5 × 7 character matrix; display memory is
 dynamic shift registers (1 K × 7) — the display is not memory-mapped.

• RAM: 16-pin 4 K dynamic type 4096 (2104); on-board capacity 8 KB,

 4 KB supplied; the system is "fully expandable to 65K" off-board.

• Power supplies: +5 V @ 3 A, ±12 V @ 0.5 A, −5 V @ 0.5 A. Input:

 8–10 V AC (RMS) @ 3 A and 26–28 V AC (RMS) centre-tapped @ 1 A.
 Recommended transformers Stancor P-8380 / Triad F31-X and
 Stancor P-8667 / Triad F40-X.

• The board draws no more than 1.5 A from +5 V and the regulator supplies 3 A, so

 1.5 A is available for expansion. At the edge connector only +5 V is regulated; the
 ±12 V and −5 V pins carry raw DC (approximately ±14 V) with no short-circuit
 protection and external regulators must be used.

• PIA register map: $D010 KBD data, $D011 KBD control, $D012 DSP data,

 $D013 DSP control.

• Monitor behaviour: RESET gives backslash then carriage return; a

 backslash alone, cursor staying on the same line, indicates bad page-zero RAM.
 Commands are line-at-a-time up to 128 characters; `.` is the range
 delimiter, `:` stores, `R` runs, ESC cancels a line and
 SHIFT-O (backarrow) backspaces echoing an underline.

Internet Archive item Apple1Manual1976.

Copyright © 1976 Apple Computer Company. Out-of-print manufacturer documentation, reproduced here for repair and preservation reference. Not freely licensed; no free licence is claimed or implied.