Tandy 1000 Technical Reference Manual

Tandy 1000
DIRECTION SELECT
Step-out
Technical Reference Manual
Step-in
STEP
Direction latch output
in U2
48tpi FDD:
Internal step pulse gen.
output in U2
Overdrive timer output
(U2,pin 19)
Motor driver inputs
PHASE A (U2,pin 21)
PHASE B (U2,pin 23)
(TP3)
PHASE X (U2,pin 22)
PHASE 8 (U ,pin 24)
tl
t2
t
t2
tl: Second step delay (3ms,approx.)
t2: Phase B or B magnetization (3.6ms,approx.)
(Fig.310) Stepping motor control circuit waveforms
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Tandy 1000 Specifications

General

Processor	Intel 8088
Processor Speed	4.77 MHz
RAM	128 KB (expandable to 640 KB)
Operating System	MS-DOS 2.11
Manufacturer	Tandy Corporation
Release Year	1984
Storage	Single or double 5.25" floppy disk drive (360 KB), optional hard drive
Sound	Tandy 3-voice sound
Ports	Parallel, Serial
Graphics	CGA (Color Graphics Adapter)
Graphics Modes	320x200, 640x200