when should a slave broadcast data?

RE: when should a slave broadcast data?

Torsten Robitzki — Thu, 13 Nov 2014 17:26:31 GMT

Hi Asbjørn, and that's exactly the configuration we've used to the beginning. The slave uses the RX_event and calls sd_ant_broadcast_message_tx() every time a RX_event is received. And this exact approache leeads to a results, where the master counts N EVENT_TXs and N/2 EVENT_RXs, while the slave counts N EVENT_RXs and N/2 EVENT_TXs.

So the obvious approache that we took first and that your are describing as the route to follow, is not working with the maximum possible bandwidth.

RE: when should a slave broadcast data?

Asbjørn — Wed, 12 Nov 2014 12:13:10 GMT

I assume you have set the channel type to be a bidirectional slave/master channel since you are able to get some packages through. Reading more closely through your text I see that you have already found the explanation, it is too late to run the sd_ant_broadcast_message_tx() on the slave side after you have received the package from the master. So the data from the slave to the master will always have to be a package behind in that sense. You have to write to the sd_ant_broadcast_message_tx() for every time you want it to. So after the RX_event on the slave you have to use the sd_ant_broadcast_message_tx() in order to send data back to the master at the next connection event.

RE: when should a slave broadcast data?

Torsten Robitzki — Tue, 11 Nov 2014 21:44:45 GMT

The channel period is 20ms. Both sides use the exactly same software and thus the same configuration of the channel period. Yes, I've search for help in the examples but found only the ANT tx/rx examples in the nRF51 SDK, but this examples implement just unidirectional communication. In this example, the master is sending, the slave is receiving. What we are trying to achive is bidirectional communication as mentioned in ANT_Message_Protocol_and_Usage_Rev_5.1 chapter 5.1 (Figure 5-2.). -> the master is sending and receiving data from the slave. The slave is receiving data from the master and sending data back. Two independent streams of data.

RE: when should a slave broadcast data?

Asbjørn — Tue, 11 Nov 2014 15:54:28 GMT

What's the timing on the ANT channel that you open. Are you using the default timing interval between events or are you changing this somehow? You should just have to setup both RX and TX side with the same parameters with regard to timing and you should see them all. Have you had a look at the ANT tx/rx example in the nRF51 SDK?