Error 8 (0x8) GATT CONN TIMEOUT On Android

[why_do_i_need_a_user_name]

NRF51422 Custom board

SD310 v3.0

Phone: LG K8 4G

Android 6.0

SDK 9.0.0 Boot-loader example

I am testing over the air DFU with our custom device.

a.) DFU using NRF Toolbox on IPhone works fine.

b.) DFU using MCP\NRF51 dongle works fine.

c.) DFU using NRF Toolbox on Android fails with "upload failed GATT error"

nRFConnect on Android can connect with our device but loses the connection after about 6 seconds and the logger captures the following error:

Error 8 (0x8) GATT CONN TIMEOUT

[Hung Bui]

Hi,

Could you clarify this: nRFConnect on Android can connect with our device but loses the connection after about 6 seconds

Was your device running bootloader firmware or your application ? Did you start doing DFU before you get the GATT CONN TIMEOUT ? Or simply connecting and let it be for 6 seconds and the timeout happened ?

Have you tried to test with other Android phone ?

I would suggest to test changing the connection parameters setting in the bootloader to increase the connection interval, I would suggest min to 30ms and max to 60ms just to check.