The TX/RX behaviour of OpenMesh?

[stephen]

I've studied the nRF OpenMesh for a couple of days, and could run the BLE_Gateway example among serval nRF51DK boards. But now, I still don't have any feeling/concept about the radio tx/rx switching behaviour. The following is my questions listed about the OpenMesh v.0.8.5,

1. Is there a simple sync mechanism existed among OpenMesh nodes?
2. Does radio or cpu ever go to sleep when running OpenMesh?
3. For radio tx, the adverting interval (mesh_interval) can be set, but how about radio rx? Is there a scan window setting, or rx alway keeps stand by for receiving data?
4. For one certain data handler, how to know the previous version data has been sent and prepare the next one immediately to get higher throughput?

Anyone can help me if you have an answer.

Thanks, Stephen

[Trond Einar Snekvik]

Hi again Stephen,

1: There's no sync behavior in OpenMesh at this point but we're looking into and discussing it in this github issue. While primary focused at large scale synchronization, I believe it can create a foundation for power consumption targetted time sync at a later stage.

2: Radio: Not really. There are short turnaround times, but the radio is on >99% of the time. CPU, on the other hand, sleeps most of the time (<10% utilization).

3: No. We'd like to do something with the time sync here, but for now, it's always on.

4: You can enable TX events for each handle, which will give you an event whenever it's transmitted. Note that transmitting the packet does not guarantee that it is received by others.

[stephen]

Okay, got it, and thanks you again. In addition, I found two addtional problems. First, it needs to add extra 6 ms delay between bc_mesh_start() and rbc_mesh_value_set(), otherwise, it would fail and go into HardFault_Handler(). 6ms delay is reasonable? If not, how to reduce it. Second, the handle pair will not re-broadcast its value next cycle after executing bc_mesh_stop() and then executing bc_mesh_start(). I suspect that handle pair would not re-broadcast unless it get the latest version again in this situation. Do you have any suggestion about these two, my Master? thanks, Stephen