BLE DFU via PC nrfutil is really slow

RE: BLE DFU via PC nrfutil is really slow

bjorn-spockeli — Mon, 05 Sep 2016 11:13:24 GMT

You can try to set the minimum and maximum connection interval defines in nrf_ble_dfu.c in the bootloader to the same value, i.e.

#define MIN_CONN_INTERVAL                    (uint16_t)(MSEC_TO_UNITS(15, UNIT_1_25_MS))            
#define MAX_CONN_INTERVAL_MS                  15                                                    
#define MAX_CONN_INTERVAL                    (uint16_t)(MSEC_TO_UNITS(MAX_CONN_INTERVAL_MS, UNIT_1_25_MS))

This should force the central on the connectivity chip to set the connection interval to 15ms and not somewhere between 15 and 30ms.

RE: BLE DFU via PC nrfutil is really slow

chewlm86 — Mon, 05 Sep 2016 10:32:51 GMT

I see. Is there a way to change these setting on the connectivity firmware?

RE: BLE DFU via PC nrfutil is really slow

bjorn-spockeli — Mon, 05 Sep 2016 09:07:28 GMT

The actual time it takes to complete a DFU will depend on the connection interval. I think that Android v6.0.0 allows for a connection intervals down to 11.25ms, and the bootloader has preferred connection parameters between 15 and 30ms. I am not sure what the minimum and maximum connection parameters are set to in the connectivity firmware, but it most likely closer to 30ms.