Hey there!

I am trying to get the metadata out using python example bu unable to fetch the meta. the execution stops at _check_error. bladerf._bladerf.InvalError: Invalid operation or parameter.
Have set _bladerf.Format.SC16_Q11_META as the format in sync_config.

rx_test.zip

Any leads on this will be highly appreciable.
Thanks in Advance.

Hello!

According to the API definition, one must send a meta object when requesting a rx with meta. That is in your line 144:

meta = device.sync_rx(buf, num)

Can you try:

meta_send = _bladerf.Metadata(
            0,
            _bladerf.MetadataFlags.BLADERF_META_FLAG_RX_NOW,
            0,
            0
        )

meta = device.sync_rx(buf, num, meta_send)

I don't have a bladeRF available right now, let me know if it fixes the issue.

Hi!

Thanks for the response! Yes, the above solution worked well.

meta_send = _bladerf.Metadata(
            0,
            _bladerf.MetadataFlags.BLADERF_META_FLAG_RX_NOW,
            0,
            0
        )

meta = device.sync_rx(buf, num, 0, meta_send)

Got this as response :

Metadata(timestamp=3, flags=2147483648, status=196608, actual_count=1024)
Metadata(timestamp=1027, flags=2147483648, status=196608, actual_count=1024)
Metadata(timestamp=2051, flags=2147483648, status=196608, actual_count=1024)
...
Metadata(timestamp=1014413, flags=2147483648, status=196608, actual_count=1024)
Metadata(timestamp=1015437, flags=2147483648, status=196608, actual_count=576)

Could you please help me with how to interpret the timestamps in order to verify no-loss?

I am trying to achieve time-stamping for each chunk of samples. Was expecting actual timestamps.

Thanks! :)

The timestamp is a counter that increases at sample rate, and it's linked to the first sample of the buffer (note that enabling a channel resets the timestamp).

If there's is no overrun flag in the status field that means that the chunk was send without drops, and if the timestamp is continuous (adding the number of samples) that means there was no gap between chunks. You can probably verify this using the loopback mode or another receiver.

I encourage you to read the documentation since this questions are answered much clearer than I can.

https://nuand.com/libbladeRF-doc/v2.5.0/sync_rx_meta.html

Got it!

I very much appreciate your help :)