Posts: 17
Registered: ‎11-29-2016

Issues forwarding 2 slaves to 1 master

We have a device for forwarding SPP data and our customer wants to extend the feature to forward data from 2 devices to a single master.


I've tried multiple strategies for handling the data, but it appears the BT121 at some point simply runs out of either processing power or RAM to handle the data flow, even with no BGAPI or serial support (I'm assuming disabling the serial port should free up the RAM used for those buffers).


Symptoms of the issue are normally that the module will allow a connection but will not create an endpoint for the connection.  Other times it might create the connection but, after a very short period of time the entire application will hang.  Other times it's connected to the 2 devices and begun forwarding, and then a large number of clearly erroneous characters will appear and then the master connection data flow stops.


I've had some success sending the data over the uart without a hang, but of course that doesn't solve the problem.


Ideally i could tune the sizes of the device and host buffers (data flow is overwhelmingly uni-directional) but that is apparently not possible.


I'm curious if there are other smart ready modules with higher available RAM limits (and better overall BGAPI performance) available or if there are any tuning tricks which might allow reliable communication.


Barring that, is it possible to put 2 BT121 modules in fairly close proximity on one PCB without interference, or is there some way of wiring 2 modules so as to avoid transmission issues.



Posts: 2,732
Registered: ‎09-01-2015

Re: Issues forwarding 2 slaves to 1 master



we don't have other Smart Ready modules available than BT121.


I'm not sure what you mean by "forwarding SPP data". Are you opening two SPP connections and streaming data from both of those connections to the single UART interface?