HP 7942 Service Manual page 68

Disc/tape drives
Table of Contents

Advertisement

DITA/CONTROl
INTERfACE BUS
(DC-IBI
[D---,
12
I
II
II
DC PDIER
fIlE of S lAX 161
12P2
1
1
I
I
I
1
I
!
I
20
I
I
1
I
I
I
I
i
I
I
1
1
"
i
I
I
I
~------------------------------------------~
, DEVICE DEPENDENT
\
CONTROLLER PCA-A2
(FRA2)
101HZ
' \
~
CLOCK
1
151HZ
GEN
r -
J2
~----~
J4
CSRS-l
/
13
"
I
/
I
eSIS-l
14
"
1
I
CDNTROl/STITUS
1
IDDRESS BUS
SEl-l
I
-
HDA
SWITCH
_
DESCRIPTION
U4B4
PROM
I
CSBO-H
-
25-29
/
1
CSB1-H
L ..
.....
TRANS-
...
"
I .
;;-aJ
1-
~
CEIVER
...
---
CDNT ROll
STA lUS
1
1
0111 8US
(
1
SND
I
'!,
CONTROLLER
1 C
&
REGISTER
DECODE
LOG I C
10-12
,.
PHASE
LOCKED
LOOP
RUI'
Rlfl<
"
1/
11
RIFI-
I C
DIS C
CONTROLLER
Ie
SKCMP-l
t - -
TRKO-L
t - -
WFll-l
I - - -
I NOX-l
W RITE
I
RRIFI-
I"
1/
!If 1-
I
r .....
:~
(
I
2 . 4 . P
~1~:h~h~1
1
~
19.20
PRE-
COMPENSATION
~
J3
H59-l
"
1/
I
HSI-l
"
1/
HS1-l
I,
1/
I
Ii
14
16
5T-506
INlERfACE
"I3P2
/
1
I
"
1
I
1
1
I
~
" 13PI
1
1
"
1
I
I
1
I
IS
I
I
Theory of Operation
7942 and 7946
13
3
0111
IS
4
CONTROL
I
15. 19.2 4.
I
DOC
'---I
PUPO
ERRORS
1-
REGISTER
REGISTER
I - - -
H50 - L I'
I
I
I
1
1
I
1
1
1
"
1
I
I
1
I
I
I
1
1
I
1
1
1
1
IIP3
I
19.34, S9,
H, 0,50
01110 -H -
lOOP liCK
SElEC
T
~
J
~ R~ER
. .
I .. - - - .
35-38
/DllIl-H
lL.....
j
. . . . . . . . . . . . . . . . . . . . . .
40 -
43
45
"
9
r .... -
I
_ _ _
,,~DRIVER ~
1
I~
1
DI5C
1
1
1
1
DAIN-l
REIO/IRIlf
DIH 8U5
/
I
,
1
OHA
~-r-----------+l
HAN 0-
/
1
DSIN-l
,
1
SHAKE
( , - . . . L - - - _ - - - - - - - I CON T R 0 L
1
OROUT-l
/
1
"
1
/
1
DSDUl-l
"
JI
0-.
51
~'11Y
I
( :
PlAl-H
POIEA DN RESET,
All
CIRCUITS,
I GND
I'S~
L _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
1 ..
,.
LA lC H
~
RDI-l
I - - -
SlEP-L
r----
DIA-l
r----
Hllf- L
r----
H51-l
---
HS4-l
-----
H51-l
---
HSO-l
-----
D50-l
--
I
I
I
1/
5K CMP-ll,
1
I
1
~
I
I
1
1
10
12
1/
I
TRKO-ll"-
(
Wf LT-l
.s..
1/
I
I
/
I
20
1
INDl-~"
1/
"-
I
/
22
RD I -l
~"
1/
1
5lfP-l
I
"
,
I
/
I
14
1/
"
I
1
26
DSO-l
I"
1/
I
I
/
I
34
DIA-L
k
1/
I
I
1
HI TE-l , ,,
?
I
I
SND
I
r : : D D
I
PINS,
lHAU 3
RE D-l
J5
-"
GREEN-l
I,
1/
I
'51
-l-l;?
8~",,,
_ _ J
lIUlT/DN-ll ME]
II
De POIER
1B
Figure 3 - 5. Disc Drive, Functional
Block Diagram, (Sheet 2 of 3)
3-37/3-38

Advertisement

Table of Contents
loading

This manual is also suitable for:

7946

Table of Contents