Appendix N Multidrop Communications - Microscan MS-890 User Manual

Multidrop Communications
Appendix N — Multidrop Communications
This appendix describes the rules for setting up a concentrator or controller to communicate
with a scanner in standard Multidrop protocol.
The diagram to the right shows a typical Multidrop network in which 1 to 50 scanners can
communicate with a host via an intermediary device, a concentrator, or a controller.
Host
Concentrator
Multidrop
Configure Scanner for Multidrop
1. With the scanner connected to the host, Retrieve Reader Settings.
2. Select Multidrop in the Protocol configuration menu.
You will see the following message:
Important: You must change your preamble and postamble characters so that they
are not CR or NUL.
This allows data to move through the concentrator without interference.
3. Click OK.
4. Next, go to Preamble Characters (still in the Protocol menu) and double-click on
Characters.
5. This will open up an ASCII character table. Select any character but CR.
6. Repeat the above process for Postamble.
7. Check the multidrop address. Enter a number from 01 to 50.
8. Right-click in the window and select Save to Reader and Send and Save.
9. Your scanner is now in Multidrop. From here on, you will need to use the concentrator
to relay commands and data between the scanner or scanners and the host.
10. Move on to Connect to Scanner via
A-34
Polled Protocol
Multidrop ONLY
RS-485 Interface
Scanner 01
Scanner 02
Scanner 03
Concentrator.
MS-890 Industrial Automation Scanner User Manual