NEC RS-232C Car Video System User Manual


 
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5.4 "Set parameter" reply
The Monitor echoes back the parameter and status of the requested operation code.
1
st
byte) STX: Start of Message
ASCII STX (02h)
2
nd
-3
rd
bytes) Result code
ASCII '0''0' (30h, 30h): No Error.
ASCII '0''1' (30h, 31h): Unsupported operation with this monitor or unsupported operation under
current condition.
4
th
-5
th
bytes) OP code page: Echoes back the Operation code page for confirmation.
Reply data from the monitor is encoded to ASCII characters.
Ex.) OP code page 02h -> OP code page = ASCII '0' and '2' (30h and 32h)
Refer to Operation code table.
6
th
-7
th
bytes) OP code: Echoes back the Operation code for confirmation.
Reply data from the monitor is encoded to ASCII characters.
Ex.) OP code 1Ah -> OP code (Hi) = ASCII '1' (31h)
OP code (Lo) = ASCII 'A' (41h)
Refer to Operation code table
8
th
-9
th
bytes) Type: Operation type code
ASCII '0''0' (30h, 30h): Set parameter
ASCII '0''1' (30h, 31h): Momentary
Like Auto Setup function, that automatically changes the parameter.
10
th
-13
th
bytes) Max. value: Maximum value that monitor can accept. (16bits)
Reply data from the monitor is encoded to ASCII characters.
Ex.) '0''1''2''3' means 0123h (291)
14
th
-17
th
bytes) Requested setting Value: Echoes back the parameter for confirmation. (16bits)
Reply data from the monitor is encoded to ASCII characters.
Ex.) '0''1''2''3' means 0123h (291)
18
th
byte) ETX: End of Message
ASCII ETX (03h)
Result OP code page
OP code
Type Max value
Requested setting
Value
STX
Hi
Lo
Hi
Lo Hi
Lo
Hi
Lo
MSB
LSB MSB
LSB
ETX
1
st
2
nd
-3
rd
4
th
-5
th
6
th
-7
th
8
th
-9
th
10
th
-13
th
14
th
-17
th
18
th