Hi all,
I'm trying to use the nRF51822 sniffer to troubleshoot my TI CC2650STK sensortag ble communication and the output is slightly confusing. The problem I am having with the sensortag is that the output I am getting from the sensor is always exactly 2 times the communication interval I set via BlueZ on my Raspberry Pi. The wireshark output looks like this:
I'm struggling to fully understand what exactly is the sequence here: which line exactly signifies the beginning of a new communication interval? Is is line 2351 ("ping" the sensor by sending an empty data PDU) or line 2353 (Rcvd Read Request, Handle : 0x003C)? Additionally, I'm a little confused why it takes two times 1(s) - my chosen connection interval - to get the data out? It looks like the slave and master always exchange empty data pdu's between each other, which isn't something I would expect - shouldn't it just be the following sequence:
Master->Slave: read request
Slave->Master: data
Thank you!
p.s. I use BluePy library (linux BlueZ stack based library) on my master device (Raspberry Pi 3B)with the following communication interval setting:
hcitool lecup --handle $HANDLE --min 800 --max 800 --latency 0 --timeout 1000