Hp 7925H Sector Sensing System, Functional Diagram - HP 7925D Service Manual

7925 Appendix A
10
SEE
READIWRITE
SYSTEM
DIAGRAM
(05)
9 > - U W G - - .
K
~
URG -----..
P2
UWG
URG
NOTES:
1. FOR LOCATION OF JUMPERS W312 AND W314, SEE FIGURE
A-16, NOTE 3.
2. REFER TO THE FOLLOWING FIGURES FOR DIAGRAMS OF
REFERENCED SYSTEMS:
INTEGRATED CONTROLLER. . A-14
MAINFRAME ASSEMBLY . . . A-15
OPERATION CONTROL SYSTEM. A-16
SPINDLE ROTATION SYSTEM. A-17
HEAD POSITIONING SYSTEM. A-18
READIWRITE SYSTEM . . . A-20
FAULT DETECTION SYSTEM. A-21
HO
B4
----.-1
111
}
SEE READIWRITE
SYSTEM D lAG RAM
' - - - - - - - - 4 -
(B3)
H2
HE,\D
REGI:;TER
SEE 01'1: IlI\TION
CONTIl()!. SYSTEM
DIMiHI\M (A3)
II·(~
H3
I
1
- - .-J
SEE OPERATION {
CONTROL SYSTEM . WRITE
DIAGRAM (A3)
DATA
OUTPUT
BUS
B4
SEE OPERATION CONTROL
SYSTEM DIAGRAM (03)
~
TARGET
SECTOR
REGISTER
SC
Q SC
' J ---__"'-----------.
A3
C
SECTOR
COMPARE
FF
SCTRG
SECTOR
COMPARATOR
. _ - - - - + - - t 0
DATA
INPUT
BUS
Bl
PHYSICAL
SECTOR
REGISTER
U3
SEE READIWFlI fE
SYSTEM DIAGIIAM
(C3)
~
BAILOUT
SEE OPERATION { IlLAD
CONTROL SYSTEM WIlITE
DIAGRAM (A3)
I W312
...... . - - - - - - - - - - - - - - - - - - - - - - - - ' 0 0 1 - - - - - - - - - - - - - - - - -------'
NOT IN PLACE
FOR 7925H
LOWER
DISC
SECTOR
COUNTER
UPPER
DISC
SECTOR
COUNTER
' - - - - - - - - - i - - - - - Q
TIMING
DECODER
TIMING
DECODER
W314
TIMING
GENERATOR
TIMING
GENERATOR
PR~;;;;;P~
---- -- - . - - --- --- ------------------ --- ------- . - ---- --- --------- ---------------------
SEE INTEGRATED CONTROLLER DIAGRAM
,..-- - - J
A .... . . . . . . ,
o
I
I
I
I
I
I
I
L
78
COUNTER
PHASE
LOCKED
LOOP
INDEX
DETECrOR
I
I
I
- - - I I
I I
I I
I
I
1--
--p_2~16
>--
SCL
~ 61t-(-:-~2----S-CL-.----tlr----l~
~--....
I
II
TP
I
!
3~
Ii
I
TP I
I
~
I
i
.~I
3
1
v),
_ _ _ _ _ _ _ _ ---.J
C~P
I
DET:C~YZ!}J
-
NDPS
-<
SYSTEM
DIAGRAM
(B8)
SERVO HEAD
SIGNAL FI LTER
LOW-PASS
FILTER
VARIABLE GAIN
DIFFERENTIAL
AMPLIFIER
AGC }
SEE
L
HEAD POSITIONING
SYSTEM DIAGRAM
(C18)
INDEX PATTERN
0*
I
1
I
I
I
1
L_
I
TRAC"i<"FoUOWE'ii'PCA-M - - - - --- - - - - - - - - - - ---
I
------.
WINDOW
I
GENERATOR
DIFFERENTIAL
PREAMPLIFIER STAGE
I
I"
~---r--- S~~ci~
- - - - - «
1,3
SECTOR 63
1
I
SECTOR SENSING SYSTEM TIMING DIAGRAM
*@ FOR AN HP 13356A DISC PACK
1 FOR AN HP 13357CE DISC PACK
REF
PRE
TEST
POINT
ACTUATOR
ASSEMBLY
' - - I
I
I
L __
-.J
A
C
o
7311-100
10
Figure A-19. HP 7925H Sector Sensing System,
Functional Diagram
A-59/A-60