Unable to receive UART-BLE from peripheral

RE: Unable to receive UART-BLE from peripheral

FormerMember — Fri, 14 Oct 2016 06:25:50 GMT

Both nRF Connect and nRF Toolbox --> UART should work for testing the UART example ble_app_uart. Both of them can write to the CCCD of the UART service and enable notifications.

"Am I right to say I don't have to change anything in the code here, but just have the client write to the CCCD of BLE-NUS before I use ble_nus_string_send?" Yes, that's correct.

RE: Unable to receive UART-BLE from peripheral

leehong — Thu, 13 Oct 2016 23:01:45 GMT

Used the nRF Connect app to turn on the CCCD of BLE-NUS then switched to nRF Toolbox to see the datastream.

RE: Unable to receive UART-BLE from peripheral

leehong — Wed, 12 Oct 2016 23:28:12 GMT

Hi Kristin, thanks for the resp. I get the basic idea that (i) the client(smartphone) establishes the connection with the server(nRF), then (ii) the client(smartphone) writes to the CCCD register of the server(nRF). Am I able to test it out using the nRF Toolbox's UART-BLE? Or am I suppose to use the nRF Connect to write to the CCCD and then switch to nRF Toolbox's UART-BLE?

Also, once my new SPI data is read to the nRF, I plan to use UART-BLE to send it over to the client. Am I able to use the ble_nus_string_send function to do so after enabling the CCCD?

Sorry, I'm getting a little lost here. Am I right to say I don't have to change anything in the code here, but just have the client write to the CCCD of BLE-NUS before I use ble_nus_string_send?

RE: Unable to receive UART-BLE from peripheral

FormerMember — Wed, 12 Oct 2016 07:20:44 GMT

To be able to transmit data from your device (server) to the phone (client), the phone will first have to enable notifications on the server side. A server is not allowed to transmit notifications unless the client has enabled it. Enabling of notifications happens after a connection has been established.

To enable notifications, the client has to write to the CCCD of the characteristic in question. Part 1 of this video tutorial introduces CCCDs at approximately 17:00, and continues to talk about data transfer/notifications from 19:30 to 22:40. In part 2 of the tutorial, the code walk through goes through how notifications are enabled at the server time, that part starts at approximately 14:50.