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3-4
Section
Connecting a Bar Code Reader
30
Item
Default Setting
Possible Settings
Baud rate
4800, 9600, 19200 bps
9600 bps
Input Method
Manual, Auto
Manual
Make the settings shown in the table below at the bar code reader. Make sure
that the baud rate, parity, stop bit, and data bit settings match the communication
settings made at the NT21. For details on the setting method, refer to the opera-
tion manual for the bar code reader used.
Item
Possible Settings
Baud rate
4800, 9600, 19200 bps
Parity
EVEN, ODD, NONE
Stop bits
1 or 2 bits
Data bits
7 or 8 bits
Preamble
STX
Postamble
ETX
RS/CS control
Available
Communication protocol
No-protocol mode
Transmission of number of bar code label digits
Transmission prohibited
Transmission of ID characters
Transmission prohibited
Bar code types
Multi-reading (all types can be
read)
Trigger switch setting
Automatic reading mode
About RS/CS Control
During bar code reading, the NT21 performs RS/CS control. When the Input
Method setting of the NT21 is set to Auto, the RS signal is turned OFF, prohibit-
ing the next input, until the read data is notified to the host.
Because of this, when the Auto setting is made, the next input is not possible
until the data is notified to the host.
However, when the setting is Auto and the RS/CS signals of the cable are
shorted, RS/CS control is ineffective. Consequently, data input from the bar
code reader to the NT21 is updated regardless of whether or not the data is noti-
fied to the host.
For details, refer to the operation manual for the bar code reader used.
3-4-3 Data Format
The data format for communication when using the bar code input function of the
NT21 is shown below.
Data
Data
Data
STX
ETX
(03
H
)
(02
H
)
The characters that are effective as data are hexadecimal codes from 20 to 7F
H
,
and the maximum data length is 40 bytes.
Data that does not follow the data format described above is invalidated and dis-
carded.
Settings at the Bar Code
Reader