[Imported] M Series Protocol-Derived Transmit Stream ID

[sbeadle]

>>Message imported from previous forum - Category:Trio Data Radios<<
User: joelw, originally posted: 2018-10-16 22:03:29 Id:44
This is a re-posting from the obsoleted (October 2018) "Schneider Electric Telemetry & SCADA" forum.

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**_jweder:
Introduction:_**

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A little-known feature of the Trio M Series radio is the User Protocol Derived Transmit Stream ID. It allows the system designer to route data packets addressed to specific devices in ways that would not otherwise be possible. This is done by telling the master site's radio to look at a specific byte of the user protocol, and use that value as the transmit stream ID. (normally only one pre-configured transmit SID is used)

As an example, presume a simplex system (one frequency used for both Tx and Rx) in which two or more repeaters are required. Normally in a system such as this all of the repeaters would transmit at the same time. Remember that they are all on the same frequency. If any remote site's radio can receive a signal from two or more of the repeaters it may hear a distorted mix of those signals. The radio would not be able to demodulate the signals and a timeout would occur. The system might work intermittently or perhaps not at all.
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A related feature which may be useful is Smart Stream ID. It may be desirable for any given radio to monitor more than one received data stream. In this case you would enable User Port Smart Stream ID, then configure a range of SID's to listen for. Eg if data is coming back from any one of several simplex repeaters, each would be using a different transmit Stream ID. Thus the radio at the Host location would need to listen for several SID's.

** Configuration Steps Required**:

**Host Radio **
· Connect to the Master (Host) radio and perform a Read.
· Configure the radio's features as required eg frequency, power output, serial ports, etc.
· Click on the Stream Setup button.
· Select User Port with Smart Stream ID.
· Enter the range of SID's the radio will listen for. Eg From 31 To 32. (for 2 repeaters)
· Click the Enable User Derived TxSID check box.
· Enter the Tx SID Offset. In Modbus the destination station is the first byte, so the offset is 0. In DF1 the destination station is the third byte, so the offset is 2.
· Click Ok, Save the configuration, then Write it to the radio.

**Store & Forward Repeater**
· Connect to the repeater radio and perform a Read.
· Configure the radio's features as required eg frequency, power output, serial ports, etc.
· Click on the Stream Setup button.
· Disable the local serial port by clicking the Disabled option. (see Note 1 below)
· Click on the Repeat/Translate Configuration button.
· In the first entry, select Repeat Range.
· In the From and To boxes enter the range of Stream ID's (based on the destination RTU/PLC station addresses) the radio will repeat. Eg From 11 To 12.
· In the second entry, select Repeat Range again.
· In the From and To boxes enter the range of SID's used by the remote radios as their Tx SID values. In the example the first repeater will repeat From 31 To 31. (only one SID) This must be unique in each repeater or both might repeat a reply message.
· Click Ok twice, Save the configuration, then Write it to the radio.

**Remote Radio**
· Connect to the Remote radio and perform a Read.
· Configure the radio's features as required eg frequency, power output, serial ports, etc.
· Click on the Stream Setup button.
· Enter the local RTU/PLC station number as the Rx SID.
· For the Tx SID, enter the value used in the second Repeat table entry of the repeater. (again, see the attached example graphic for further details)
· Click Ok, Save the configuration, then Write it to the radio.

**Note 1**: This configuration will disable the Store & Forward repeater's local serial port, thus no local RTU or PLC may be connected. In an M Series radio, one Repeat may be done with no penalty as internal circuitry is available to handle it. A second Repeat however requires use of the user serial port circuitry. If it is desired to connect a local PLC or RTU then the second Repeat Range must be replaced with a Translate entry instead. Translate does not require hardware. Instead it changes the SID before resending the message (eg from 31 to 41) thus the Master radio's Rx SID From and To values will also need to be changed to receive these new SID's.

**Note 2**
: The User Derived Tx Stream ID feature is meant to work with 8 bit (1 byte) addresses. It may work with Extended Modbus, DNP3 or other protocols if the offset points at the LSB (least significant byte) and if the MSB (most significant byte) is not used. (eg only max 255 addresses)

Attached file: (editor/0w/nqlfh6natiq5.jpg), M Series User Derived TxSID.jpg File size: 184689