Personal page of Konjengbam

Points to Ponder

Below is a usage scenario of one Modbus Bluetooth Adapter (VW3A8114), available from Schneider Electric USA. The idea behind this Adapter is to primarily allow process/field Engineers to access data from Drive controllers or PLCs, from a location deemed hazardous.

What if we take this further to produce a device which can be configured either as a Serial or Ethernet I/P point, rather than this scheme below allowing only RJ45? I think that would be great. Anyone done anything on this front?

I would expect the MBAP message from this Adapter OTA be carried by an L2CAP packet through a dedicated PSM - the MB ADU will remain undiminished/unmodified and without any bias carries the same as L2CAP payload. Also, in a new design this new Adapter when placed in the vicinity of one other Adapter (as M/S Bluetooth roles) should provide as Bridge to traditional media, such as RJ45, RS232/485 (Serial). What this means is offering a great deal of flexibility - Bluetooth enabled HMIs (Handheld or Laptops as show below) should be able to communicate directly with the Adapter + Traditional HMI should be able to operate in PnP environment when placed two such Adapters in Bluetooth piconet (Bridge sort of) mode.

This enhancement could be a future work if not realized yet, and IMHO I personally see possibility of market area in Chemicals/Nuclear and allied areas. Takers? Caution may be made here that if Bluetooth fails, lives of Engineers and people at large are at stake. Perhaps, deployment of this nature can be made as optional component providing the possibility of another read-off/control point and NOT completely eradicating the wired communications.

“Bluetooth adopter, technology enabler and innovative thinking”

The Bluetooth portion may be implemented as another L2CAP custom protocol or directly carried via HCI or LM/LC, going low to remove stack overhead (doing so will help achieve latency results also).