Configuring the 2760-rb interface module – Rockwell Automation 2755-SNx Adaptascan Bar Code Readers User Manual
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15–6
Downloading Match Codes via DH485 using a PLC-5 Processor and a 2760-RB Module
Publication 2755-6.8
Using the 2760-RB Module, Revision H or Above, with the New
Generation PLC-5 Processor
When the 2760-RB, revision H or above, is used with the new
generation PLC-5 processors in a local chassis, there is a possibility
that the PLC will not see the BRR bit from the 2760-RB. For the
PLC-5 to see the BTR bit, an odd number of image scans must occur.
To ensure that the BTR instruction sees the BRR bit (bit 13) you
must place an Immediate Input Instruction addressed to the BRR bit
in another rung just before the Block Transfer Read (BTR) rung.
This ensures that the BRR bit is seen by the NP-5 processor.
| BRR BT7:5 BT7:25 000 |
+–––]/[–––––]/[––––––]/[–––––––––––––––( IIN )––––––––––––––––+
| |
| BTR |
| BRR BT7:5 BT7:25 +––––––––––––––––––––––+ |
+–––] [–––––]/[––––––]/[–––––––––+Rack 0| |
| EN EN |Group 0| |
| |Module 0+––O––+
| |Control Block BT7:5| |
| |Data File N7:200| |
| |Length 0+––O––+
| |Continuous N| |
| +––––––––––––––––––––––+ |
| |
| |
| Write BTW |
| Data BT7:5 BT7:25 +––––––––––––––––––––––+ |
+–––] [–––––]/[––––––]/[–––––––––+Rack 0| |
| EN EN |Group 0| |
| |Module 0+––O––+
| |Control Block BT7:25| |
| |Data File N7:400| |
| |Length 0+––O––+
| |Continuous N| |
| +––––––––––––––––––––––+ |
| |
| |
| |
| |
Note: BTR must come before BTW.
Refer to your PLC-5 user manual for detailed information on using
the PLC-5 programming software.
The configuration screens for the 2760-RB should be entered exactly
as shown. These parameters then need to be saved.
Both the bar code reader and the 2760-RB module are configured to
send and recognize the Carriage Return
[Cr]
, Line Feed
[Lf]
characters to identify a message. When the 2760–RB senses
information entering Port 1, it will look for the Cr, Lf. When it sees
these trailers, it will Block transfer read (BTR) the preceding bar
code data into the PLC program.
Configuring the 2760-RB
Interface Module