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Chapter 6: Serial Control
Special characters:
ACK
0x06
NAK 0x15
STX
0x02
ETX
0x03
CR
0x0D
ESC
0x1B
HTAB 0x09
LF
0x0A
Sequence of a Data Communication
Table 6-1. Data communication sequence.
ServSwitch KVM DKM FX
Control CPU
—
1. Send a command
2. Acquire a command, process a
command, block further commands.
—
3. a) Errors occurred: <NAK>
b) No errors: <ACK><ECHO>
c) Optional: Reply telegram with data
—
—
4. a) Repeat telegram
b) Next command
c) Receive and process the repeat telegram
NOTE: The serial interface can be blocked while OSD is open.
Switching Functions Telegrams
Table 6-2. Input port’s request for output port.
Bytes
Description
Coding
1
Control character
0x1B
1
Server indentification
0x5B
1
Command
0x42
2
Total length of telegram (7 bytes, binary)
0x07 0x00
2
Requested output port (binary, 1…max. ports)
0x01 0x00 (for port 1) to 0x120 0x00 (for port
288)