title: Raspberry Pi3 BLE Central device updating BLE connection event length with value 0
body: <p>i would appreciate if someone can explain one issue i'm experiencing with Raspberry Pi 3 model B acting as a Central device on a BLE connection with a Peripheral device, when updating connection parameters, and in particular with the connection event length.</p>
  
  <p>After successfully connecting both devices and enabling notifications on the Central device using hcitool/gatttool commands i started receiving notifications on the Raspberry Pi3 model B, in particular, it receives 5 BLE packets with notified values per connection interval according to the default connection parameters. Once both devices are connected, i update the connection parameters in order to set, among other parameters, the CE length to 1 (0.625ms) using the following hcitool command (according to the answer i received from the thread <a href="https://stackoverflow.com/questions/46847750/raspberry-pi3-ble-as-central-device-receiving-just-one-packet-per-connection-int">Raspberry Pi3 BLE as Central device receiving just one packet per connection interval - gatttool/hcitool</a> :</p>
  
  <p>sudo hcitool cmd 0x08 0x13   0x40 0x00   0xFF 0  0xFF 0   0 0   0x60 0   0x01 0  0x01 0</p>
  
  <p>Once the connection parameters are updated, i checked that the Raspberry Pi3 model B starts receiving just 1 BLE packet per connection interval, which is the expected behavioral. However, in case i update the connection parameters to set the CE length to 0 using the same procedure, the Raspberry Pi3 model B starts receiving 5 BLE packets with notified values per connection interval, which seems not to be coherent with the CE length value. </p>
  
  <p>Could anyone give me an explanation of that issue?</p>
  
  <p>Thanks</p>