Adjusting the connection parameters in 6LoWPAN applications

[StefanHri]

My setup consists of a Raspberry pi and a PCA10056 dev-board (NRF52840). I followed the instruction from here in order to set up the Raspberry pi as boarder router and connect to the NRF52. This works fine for me. Now I want to adjust the connection parameters: connection interval, slave latency and the number of packets per connection event. How can I do that? On the NRF52 chip I use the coap example from nRF5_SDK_15.3xx/examples/iot/coap/ipv6.

[Jared]

Hi,

The BLE connection variables can be found and adjusted in the config file of the project sdk_config.h

Regards

Jared

[StefanHri]

Hi,

can you point me to the concrete macros? I have tried to change CONFIG_MODE_MAX_CONN_INTERVAL and CONFIG_MODE_MIN_CONN_INTERVAL but this has no effect. 

Is it possible to control the number of exchanged packets per connection event from the slave? Or this is something which the master (in my case the Raspberry) only controls?

Thank you

Stefan

[Jared]

Hi,

The macros are:

Slave Latency: 

#ifndef CONFIG_MODE_SLAVE_LATENCY
#define CONFIG_MODE_SLAVE_LATENCY 6
#endif

Connection interval:

#ifndef CONFIG_MODE_MIN_CONN_INTERVAL
#define CONFIG_MODE_MIN_CONN_INTERVAL 6
#endif

#ifndef CONFIG_MODE_MAX_CONN_INTERVAL
#define CONFIG_MODE_MAX_CONN_INTERVAL 24
#endif

Number of packets:

#ifndef NRF_SDH_BLE_GAP_EVENT_LENGTH
#define NRF_SDH_BLE_GAP_EVENT_LENGTH 6
#endif

The central decides the connection parameters during connection establishment, while the peripheral can only propose them. How do you see that the change has no effect? Do you have a spare nRF52 DK that you can use as a sniffer and provide a sniffer log of the connection establishment?

Regards

Jared