Scan request packet

RE: Scan request packet

Susheel Nuguru — Wed, 03 Feb 2016 08:57:22 GMT

Sorry for answering this late, you might have already figured it out. SCAN_REQ PDU is set completely by softdevice depending on previous settings of scanner device address and the advertiser device address from which scanner wants to get more data.

RE: Scan request packet

Susheel Nuguru — Thu, 16 Apr 2015 07:37:01 GMT

SCAN_REQUEST is totally handled by central as the SCAN_REQ PDU has only two fields. copy paste from the spec

"The Payload field consists of ScanA and AdvA fields. The ScanA field shall
contain the scanner’s public or random device address as indicated by TxAdd.
The AdvA field is the address of the device to which this PDU is addressed.
The AdvA field shall contain the advertiser’s public or random device address
as indicated by RxAdd.

Note: This packet does not contain any Host Data." you can change ScanA field by changing device address of central but nothing more. What are you trying to achieve by wanting to modify scan request PDU?

RE: Scan request packet

Swetika — Thu, 16 Apr 2015 07:08:15 GMT

My question is with respect to Central. The central runs a active scanner so the Advertising packets are received and SCAN_REQUEST is sent and SCAN_RESPONSE is received from peripheral and then the data is sent to the application. Can we modify SCAN_REQUEST packet sent by central or it is totally handled by softdevice.

RE: Scan request packet

Swetika — Thu, 16 Apr 2015 07:08:05 GMT

Here Application layer means user code.My question is with respect to Central. The central runs a active scanner so the Advertising packets are received and SCAN_REQUEST is sent and SCAN_RESPONSE is received from peripheral and then the data is sent to the application. Can we modify SCAN_REQUEST packet sent by central or it is totally handled by softdevice.

RE: Scan request packet

Susheel Nuguru — Wed, 15 Apr 2015 19:13:45 GMT

Edited:

Yes, once you have created the scan response packet, you can change it again any number of times.

RE: Scan request packet

John — Wed, 15 Apr 2015 17:45:52 GMT

I'm not sure what you mean by application layer. You can create a scan request packet just like you create an advertising packet and put any data in it as long as the stack can encode it properly.