Printf ( UART ) causing TWI not to work

[Nerdwolf]

Hi all,

I had a working TWI connection combined with BLE advertising. When I added uart code for printing to putty this TWI connection was no longer functional.

So I deleted the added UART code and discovered the TWI connection stopped working as soon as I open a serial connection in putty( 38400 baud, COM7). Even when nothing in my code even metioned uart connection using usb. When I unplug my usb connection to my nRF51 DK and reconnect ( and thus disabling putty ) TWI starts working again.

My guess is it has something to do with priorities?

Kind regards,

Nils

[Nguyen Hoan Hoang]

Check to see if your TWI and UART are using the same GPIO pins. It looks like pins conflict.

[Nerdwolf]

Thanks alot! I was not aware of the fact that the uart over USB was also occupying the physical pins 8,9,10 and 11. It was indeed a stupid pin conflict , all works fine now! You made my day ;)

[syntroniks]

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