Fast Connection Intervals

[Ken]

We are attempting to perform an OTA and as such want to transfer a large amount of data as quickly as possible.

When I attempt to transfer the data with connection intervals any quicker than 25ms, the connection drops after a period of time. If I transfer with connection intervals of 25ms, the complete OTA image is transferred.

We are transferring between 2 embedded devices, so neither Android or iOS is involved in the transfer process.

We have been successful transferring OTA images with intervals of 7.5ms using another BLE Silicon vendor. That same chip is currently running as the master, with our new nordic board running as the peripheral.

Any way that we can operate at the max connection intervals? We are running SD132 on a nrf52832

[Hung Bui]

Hi Ken,

Could you capture a sniffer trace ?

Please try to debug the bootloader and check where it crashes (you need to set the optimization level to 0)

We need to check how many packet is sent during a connection event. If the data stream is too high that it's faster that the speed of writing to flash we will have buffer overflow.

In the legacy bootloader, we usually tested with 11.25ms, I'm not 100% sure which is the minimum connection interval we tested with the secure DFU.