nrf_serial - how to tell available TX buffer space BEFORE using nrf_serial_write()

[eyalasko]

Hi, 

I'm using nrf_serial 'object' in order to communicate nRF52832 with an external device.

As I work in non-blocking mode I need to verify if there's available space to send a whole message or not send it all. In any case, I shouldn't send a partial message.

I understand that nrf_serial_write()  returns the actual number of bytes queued (sent?) and if its shorter than the full message length it means that only part of the message was sent which is undesirable.

Is there a way to tell in advance if the full message can be queued(sent?) or not (and avoid dealing with partial message queuing(sending)) ?

Thanks

[Vidar Berg]

Hi,

That is correct, nrf_serial_write() returns the number of queued bytes. You can enable the event handler to get a callback when the data has actually been transferred.

The serial library does not seem to expose an API for checking available queue size, but you can use nrf_queue_available_get() from queue module instead:

      available_buffer = nrf_queue_available_get(serial_queues.p_txq);