Updating advertising data between iBeacons and AltBeacons

[zkarim]

I am able to switch between two beacon types i.e. iBeacon and a manufacturer's specific beacon when they are both the same length.  I am having trouble switching between an AltBeacon, 27 bytes in length and a 26-byte iBeacon.  It seems to crash the SD.  

I am able to switch once from AltBeacon to iBeacon, but then when I attempt to switch back to the AltBeacon, the payload is truncated, and an AltBeacon is not received/recognized. 

I am using these functions to update the advertising data.

err_code = ble_advdata_encode(&advdata, m_adv_data.adv_data.p_data, &m_adv_data.adv_data.len);
APP_ERROR_CHECK(err_code);

err_code = sd_ble_gap_adv_set_configure(&m_adv_handle, &m_adv_data, NULL);
APP_ERROR_CHECK(err_code);

This is the v16 SDK.

[Vidar Berg]

Hello,

Please make sure m_adv_data.adv_data.len is always re-initialized to the default length prior to calling ble_advdata_encode().The p_len input for ble_advdata_encode() is also used to output the size of the encoded data, which may explain why data gets truncated when trying to encode the larger AltBeacon payload.

Best regards,

Vidar

[zkarim]

Hi,

What is the default length?  Is it 31? I refresh it to the length of the block that I am encoding (24 for AltBeacon and 23 for iBeacon).

Thank you,

Zia

[Vidar Berg]

Hi,

Yes, the default length is 31. Please try to pass 31 as the input length when encoding the AltBeacon data, then check what the length of the encoded data becomes.

Best regards,

Vidar

[zkarim]

Yes, that worked perfectly.  Thank you.

[zkarim]

The length was modified to 30 for iBeacons.  Hence that AltBeacons were being truncated when I switched back to transmitting them.