RE: onread() event in SDK17

kdu — Thu, 14 Oct 2021 11:57:05 GMT

Okay, I got it.
I modified my code and it now works as expected.
Thanks for that.

// Add the VersionString characteristic.

uint8_t VersionString[16] = {"01.02.03.04"};

memset(&add_char_params, 0, sizeof(add_char_params));
add_char_params.uuid = VERSION_STRING_CHAR_UUID;
add_char_params.uuid_type = p_cus->uuid_type;

add_char_params.init_len = strlen(VersionString);
add_char_params.max_len = add_char_params.init_len;
add_char_params.p_init_value = VersionString;

add_char_params.char_props.read = 1;
add_char_params.read_access = SEC_OPEN;

err_code = characteristic_add(p_cus->service_handle, &add_char_params, &p_cus->version_string_char_handles);
if (err_code != NRF_SUCCESS)
{
return err_code;
}

RE: onread() event in SDK17

Einar Thorsrud — Wed, 13 Oct 2021 12:46:07 GMT

Hi,

There should not be any problems having characteristics with only read properties. Could it be that you somehow forget or fail to update the value, so that the init value is still used when you test? You can se an example of only read in for instance the implementation of the GLS service (SDK 17.1, around line 249 in components\ble\ble_services\ble_gls\ble_gls.c).

If you want an event on read you need to use authorized read, as without it this is handled by the stack without notifying the application. See this thread for details.