Tandy 1000 SL Technical Reference Manual page 276

TABLE OF CONTENTS
T i t l e P a g e
SECTION 2 THEORY OF OPERATION
.........................................
2 0 0
2-1 CONSTRUCTION AND FUNCTION
........................................
2 0 1
2-1-1 G e n e r a l B l o c k Diagram
..........................................
2 0 1
2-1-2 M e c h a n i c a l S e c t i o n
.............................................
202
2-2 CIRCUIT DESCRIPTIONS
.............................................
207
2-2-1 Read W r i t e C i r c u i t
.............................................
207
2-2-1-1 Mode
s e l e c t o r
................................................
209
2-2-1-2 Read c i r c u i t
.................................................
2 1 1
2-2-1-3 Write c i r c u i t
................................................
213
2-2-1-4 Low v o l t a g e s e n s o r
...........................................
215
2-2-1-5 F u n c t i o n a n d o p e r a t i n g waveform of
r e a d w r i t e L I S t e r m i n a l s
..............
216
2-2-2 C o n t r o l C i r c u i t
................................................
224
2-2-2-1 S t r a p c i r c u i t
................................................
226
2-2-2-2 F r o n t LED c o n t r o l c i r c u i t
....................................
227
2-2-2-3 Head load c o n t r o l c i r c u i t
....................................
228
2-2-2-4
Write/erase
c o n t r o l c i r c u i t
..................................
2 3 1
2-2-2-5
Motor
o n
gate
................................................
233
2-2-2-6 Ready d e t e c t o r
...............................................
234
2-2-2-7 S t e p p i n g m o t o r c o n t r o l c i r c u i t
...............................
237
2-2-2-8 T r a c k c o u n t e r
................................................
2 4 1
2-2-2-9 RD/INDEX g a t e
................................................
242
2-2-2-10
Door-close
c i r c u i t
..........................................
243
2-2-2-11 O t h e r t e r m i n a l s a n d f u n c t i o n o f c o n t r o l LSI
.................
244
2-2-3 S e r v o C i r c u i t
..................................................
246
2-3 FUNCTION
OF
TEST POINTS
AND
VARIABLE RESISTORS
...................
247
2-3-1
F u n c t i o n
of
T e s t P o i n t s
........................................
248
2-3-2 F u n c t i o n of Variable Resistors
.................................
253