Hitachi VT-FX795A, Service Manual, Page: 66 / 69

22
8 IC PIN FUNCTION DESCRIPTIONS
IC501( SERVO / SYSTEM CONTROL IC )
“H”
≥
4.5V, “L”
≤
1.0V
Pin
No. IN/
OUT
Signal
Name
Function
Active
Level
1 IN P-DOWN -L
Power
Voltage Down
Detector
Signal
L
2 IN
REC-SAF-
SW
Recording Safety
SW Detect (With
Record tab = ”L”/
With out Record
tab = ”H”)
H/L
3 IN
T-REEL
Take Up Reel
Rotation
Signal
PULSE
4 - N.U. Not Used -
5 IN
REMOCON-
IN Remote
Control Sensor
L
6 OUT
DISPLAY-
CLK
7seg. Driver IC
Clock Control
Output Signal
H/L
7 OUT A-MUTE-H
Audio Mute Con-
trol
Signal
(Mute = “H”)
H
8 OUT
DISPLAY-
DATA
7seg. Driver IC
Data Control Out-
put Signal
H/L
9 OUT
DISPLAY-
ENA
7seg. Driver IC
Enable Control
Output Signal
L
10 - N.U. Not Used -
11
OUT TRICK-H
Special Play-
back= “H”
H/Z/L
12
IN/
OUT
IIC-BUS
SDA IIC BUS Control
Data
H/L
13 OUT
IIC-BUS
SCL IIC BUS Control
Clock
H/L
14 - N.U. Not Used -
15 -
N.U. Not Used
-
16 OUT
INSEL/
ST-SL
Input Selector
Control Signal
(EE/Rec)/Still/
Slow
(Playback)
H/Hi-z
/L
17 -
N.U. Not Used
-
18 OUT RF-SW
Video Head
Switching Pulse
H/L
19 OUT D-V SYNC
Dummy
V-sync Output
H/Hi-z
20 IN RESET
System Reset
Signal
(Reset=”L”)
L
21 OUT
LM-FWD/
REV
Loading Motor
FWD/ REV Out-
put
H/Z/L
22 OUT P-ON-L
Power On
Signal to
Low
L
23 OUT D-PB-L
Playback Instruc-
tion Signal
L
24 OUT D-REC-H
Delayed Record
Signal
H
25 OUT Hi-Fi-H-SW
HiFi Audio Head
Switching Pulse
H/L
26 OUT SP/LP/SLP
Top Speed Select
Signal (SP=”L”/
LP=”Z”/SLP=”H”)
H/Z/L
27 OUT C-F/R
Capstan Motor
FWD/REV Con-
trol Signal
(FWD=”L”/
REV=”H”)
H/L
28 OUT C-CONT
Capstan Motor
Control Signal
PWM
29 OUT D-CONT
Drum Motor Con-
trol Signal
PWM
30 - N.U. Not Used -
31 - VDD VDD -
32 OUT OSCO
Main Clock Out-
put 14.31818MHz
-
33 IN
OSCI
Main Clock Input
14.31818MHz
-
34 - Vss VSS
35 IN
XI
Sub Clock Input
32.768 MHz
-
36 OUT XO
Sub Clock Out-
put 32.768 MHz
-
37 IN
SXI
Operation Mode
Selecting Input
Signal
-
38 OUT VIDEO-OUT
Composite Video
Signal Output
-
39 - Vss2 Vss2 -
40 IN VIDEO-IN
Composite Video
Signal Input
41 IN C-SYNC
Composite
Synchronized
Pulse
PULSE
Pin
No.
IN/
OUT
Signal
Name
Function
Active
Level