Allen-Bradley Series B

Chapter 3
Host Computers and Display Terminals
3–2
The decoder’s ability to transmit decoded bar code data to a display terminal
can be enabled or disabled. If your host computer echoes all received data,
you should disable the Display Terminal port using the Disable Terminal
Port configuration bar code symbol. If you do not disable the Display
Terminal port you will receive duplicate messages, one from the host and the
other from the decoder. This function’s default setting is Display Terminal
Port Enabled.
When the decoder decodes a bar code symbol, it will transmit the decoded
data to the host. When the host receives the data, it may echo the data
through the decoder’s Display Terminal port, to the attached display
terminal. Refer to Figure 3.1.
Figure 3.1
Display Terminal Port Disabled
Bar code data entered
on keyboard
Host
Computer
Display
Terminal
Echo of decoded Bar
code data
Configuration
Commands
Decoder
Decoded Bar code
data
Echo of decoded Bar
code data
Transmit
Receive
Host Decoder and
Display Terminal
Display Terminal Host
Decoder Host
Use this mode if your host computer does echo all data transmissions to
local terminals.
Note: With the Display Terminal port disabled, all escape sequences sent to
the decoder will also be sent to any local terminal connected to the decoder.
Make sure these escape sequences will not affect your terminal’s operation.
Note: If the decoder receives a Show Configuration command, the
configuration display screen will be sent only to the Host Computer port.
Display Terminal Port Disabled