Black Box ServSwitch DKM FX - Special Characters

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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฀FXControl฀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)