WT51822-S4AT UART problem. Board can receive data but not send.

RE: WT51822-S4AT UART problem. Board can receive data but not send.

samuel.zetterlund — Mon, 23 Apr 2018 05:36:57 GMT

I have one question though... The SDK example did have APP_IRQ_PRIORITY_MID. Is that correct then? Does it work having that setting with other boards? Why did my fail?

RE: WT51822-S4AT UART problem. Board can receive data but not send.

Joakim Jakobsen — Thu, 19 Apr 2018 13:24:10 GMT

Thats great! I'm glad you were able to solve it.

And thanks for sharing the solution! Now others in the community can benefit from your answer if they face the same issue.

Best regards,
Joakim.

RE: WT51822-S4AT UART problem. Board can receive data but not send.

samuel.zetterlund — Wed, 18 Apr 2018 14:50:24 GMT

Hi Joakim,

Thanks for your reply. I compared the sdk10 example with the sdk12 and found that they differed in the APP_UART_FIFO_INIT function. The sdk10 had APP_IRQ_PRIORITY_LOW whilst sdk12 had APP_IRQ_PRIORITY_MID.

I changed that and now the chip can send! I'm so happy right now! This has really bothered me.

RE: WT51822-S4AT UART problem. Board can receive data but not send.

Joakim Jakobsen — Wed, 18 Apr 2018 13:08:47 GMT

Hi!

Is it possible that you haven't enabled notifications in your modified code?

Take a look at this case that might be helpful.

https://devzone.nordicsemi.com/f/nordic-q-a/9800/sending-data-over-ble/36332#36332

Cheers,
Joakim.