Function Of Each Short Plug - Hitachi 902 Service Manual

Function of Each Short Plug

Designation
of Short Pin
IF Selection of how to change recording capacity mode
T1
IF
T2 O
S
S
S
S
O
Note:
H2 Selection of HIGH DENSITY signal output pin
H4
H2
S
O
O
T1 T2
O O 2 modes (2.0/1.0 MB)
Automatic changeover with inserted disk
2.0 MB :
1.0 MB :
S O 2 modes (2.0/1.0 MB)
Changeover with MODE SELECT signal
2.0 MB :
1.0 MB :
S S 2 modes (2.0/1.0 MB)
Changeover with MODE SELECT signal
2.0 MB :
1.0 MB :
O O 3 modes (2.0/1.6/1.0 MB)
Changeover with inserted disk plus MODE SELECT signal
2.0 MB :
1.6 MB :
1.0 MB :
O S 3 modes (2.0/1.6/1.0 MB)
Changeover with inserted disk plus MODE SELECT signal
2.0 MB :
1.6 MB :
1.0 MB :
O S 2 modes (1.6/1.0 MB)
Automatic changeover with inserted disk
1.6 MB :
1.0 MB :
The recording capacity mode is changed over with the logic level ("H"/"L") of
MODE SELECT signal.
H4
O Output to J1-2 pin
S Output to J1-4 pin
O Not output (open)
Function
Function
When HD disk is used
When DD disk is used
When MODE SELECT signal is "HIGH"
When MODE SELECT signal is "LOW"
When MODE SELECT signal is "LOW"
When MODE SELECT signal is "HIGH"
When HD disk is used and MODE SELECT
signal is "HIGH"
When HD disk is used and MODE SELECT
signal is "LOW"
When DD disk is used regardless of MODE
SELECT signal
When HD disk is used and MODE SELECT
signal is "LOW"
When HD disk is used and MODE SELECT
signal is "HIGH"
When DD disk is used regardless of MODE
SELECT signal
When HD disk is used
When DD disk is used
Function
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