Hello,
yesterday I got a Thingy:52 device at an event held in Frankfurt/Germany. At home I've tested the DFU for the latest firmware and observed that the image was transfered at a very low speed. The image was transfered with 0.4 kByte/second. I've the BLE packets logged at the smartphone and found the following:
- In the LE Connection Complete Event I've seen that the connection interval was set to 48.75ms.
- Later the Thingy (peripherial) sends the Connection Parameter Update Request with connection interval set to 15ms-30ms. The smartphone (central) accepts this request by sending Connection Parameter Update Response.
- After that the complete firmware will be transmitted packet by packet in the connection interval. But only one 20 byte packet in one connection interval. And the interval is 40-50ms in reality.
That results in 45ms/20bytes or 0.4 kByte/second transfer speed. Why do I have so low transfer speed?
The smartphone is a Samsung Galaxy S4 mini (GT-I9195).
Thanks in advance