
Serial Communication
Output Types
VT200/220 Technical Manual, Rev 1.00.01
56
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TM-VT200/220-EN
EDP Data Block Composition
Character/s Description
STX (02 h)
Start of transmission.
ASCII (any)
ASCII data identical to the data printed.
ETX (03 h)
End of transmission.
BCC
Block check character (XORSUM of all data characters STX, ETX inclusive).
6.3.8
Remote Printer Output
Works with Port 2 (RS232 or RS485). Used to transmit the data printed on the local
printer to a remote printer. No handshake is required.
6.3.9
Master-Slave Protocol Output
Works with Port 2 (RS232 or RS485). By setting port 2 output method (parameter
3.t
)
to any number between 65 and 89, you specify that the indicator should participate in
a network of several indicators. The number set in
3.t
is this indicator’s network
address.
Master-Slave Commands
Port 2 (RS232, RS485)
List of File Types (Commands)
Command Hex Description
Time Slave
Response
?
3F
UPLOAD WEIGHT & STATUS
50 ms
WEIGHT
@
40
RESET
SLAVE
15ms
NONE
K
4B
DOWNLOAD KEY
0.1 ms
NONE
? Upload Status
It is the main command used to poll the SLAVE(s), which reply with the current
weight being measured or with a message if bit 0 of the status byte is ‘1’. In the
normal state the SLAVE will respond within 3-4 character time.
(e.g. with 9600 baud, character time
≈
1 msec, the master should expect reception of
STX from the SLAVE within 5 msec after the ETX was transmitted from the master).
Master Transmission
STX ADD ?
0 BCS2 BCS1 ETX