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ba_aed104_8_e.doc
7.9
Examples of communication
Settings for the bus mode (only AD104-R5):
The AED is able to work in a bus with up to 32 modules. A prerequisite for this is that each AED is connected to
the bus through a RS-485 interface driver. In this case each AED works as slave, i.e. without request by the bus
master (e.g. PC or PLC), the AED remains inactive on its transmission line. An AED is selected by the master
via the command SELECT (S00...31). Therefore it is absolutely necessary to enter a communication address for
each AED before the bus coupling. Naturally each address in the bus may be allocated only once.
There are two ways to entry the adrres for communication:
1. Connect AED consecutively to the bus:
- Connect first AED to the bus line (The factory setting is ADR31, baud rate 9600)
- Initialize the interface of the master with 9600 Bd, 8, e,1
- Output command ;S31;
- Set wanted address with the command ADR (e.g. ADR01;)
- Select AED with the new address: ;S01;
-
Store address nonvolatile with the command TDD1;
-
Connect next AED to the bus, output ;S31;, set ADR02, etc.
or
2. All AED are interfaced to the bus
:
- Read off manufacturing number of the AED (5-digit) (1st AED: xxxxx, 2nd AED: yyyyy, ...)
- Initialize interface of the master 9600 Bd, 8, e,1
- Output broadcast command ;S98;
- Set wanted address with the command ADR (e.g. ADR01,”xxxxx”; )
- Set wanted address with the command ADR (e.g. ADR02,”yyyyy”; ), etc.
- Store addresses nonvolatile with the command TDD1;
Important Note
With S98; no AED answers, but each AED executes the command.
If there is no communication, then the address or the baud rate can be incorrect.
After successful setting of all addresses and with uniform baud rates, the bus is ready. Now it must be
determined how the measured values are read out.
With the measured value output via the command MSV?;, the output format must be set previously in all
modules:
1.
Output broadcast command S98; (all AED execute the command,
but transmit no answer)
2. Output command for the output format (e.g. COF3; for ASCII output)
3. Command TDD1; if this setting should be stored protected against
power failure.