How to send simple string data ?

RE: How to send simple string data ?

Vroon — Tue, 05 Mar 2019 01:27:01 GMT

Hi, is there a way I can push this data out via UART and view it in putty?

RE: How to send simple string data ?

kphalak — Thu, 17 May 2018 20:00:12 GMT

Use the typecast (uint16_t *) before length

RE: How to send simple string data ?

luiskjuarez — Wed, 18 Apr 2018 03:48:33 GMT

Hi, in the function "ble_nus_string_send" the length cause a NOTE when i compile, the function expected a pointer, Will this cause me problems?

This is the note that generate

opt/nrf52/components/ble/ble_services/ble_nus/ble_nus.h:206:10: note: expected 'uint16_t * {aka short unsigned int *}' but argument is of type 'int'
uint32_t ble_nus_string_send(ble_nus_t * p_nus, uint8_t * p_string, uint16_t * p_length);
^~~~~~~~~~~~~~~~~~~

RE: How to send simple string data ?

Bndit — Mon, 15 May 2017 16:51:32 GMT

Thanks a lot ! works.

RE: How to send simple string data ?

erltot — Mon, 15 May 2017 13:23:10 GMT

This is from the ble_peripheral/ble_app_uart example in SDK 12.2 in my case, I guess it's not very different from SDK13.

Simple equivalent of hello world:

/**@snippet [Handling the data received over BLE] */
static void nus_data_handler(ble_nus_t * p_nus, uint8_t * p_data, uint16_t length){
    if(p_data[0] == '?'){
        unsigned char data_arr[20] = {"Hello world!\t-Pong!\n"}; // 20 byte msg
        ble_nus_string_send(&m_nus, data_arr, 20);
    }
}

p_data[0] contains the first character in whatever you recieved from your phone, in this case if it's a "?" it replies with a string..

I prefer to use nRF Toolbox on my iphone with the UART profile for testing

From here it was fairly easy to go to strtok() and compare strings/characters in switches to handle incomming text, it's not so pretty but it works.

Screenshot from phone:

RE: How to send simple string data ?

Sigurd — Mon, 15 May 2017 07:28:14 GMT

Hi,

Where are you calling your function sendBluetoothData(tosend,4) ? in uart_event_handle()?

Also take a look at the ascii table for how the nRF-Toolbox UART app will display your data. You are here sending "Dec", and it will be displayed as "Char" in the app.