Invalid parameter error returned on sd_ble_gattc_char_values_read()

RE: Invalid parameter error returned on sd_ble_gattc_char_values_read()

TheThirdFriend — Thu, 08 Sep 2022 07:15:47 GMT

Thank you so much. I used sd_ble_gattc_read() and it's working. also sd_ble_gattc_char_values_read() worked with two handles. You made me happy 😃

RE: Invalid parameter error returned on sd_ble_gattc_char_values_read()

Kenneth — Wed, 07 Sep 2022 09:12:43 GMT

NRF_ERROR_INVALID_PARAM can be returned in two cases:

- provided handle_count is too big and cannot fit in ATT_MTU
- provided handle_count is less than 2

In your case I can see the hndl count is only 1, so this is causing the issue. Also see:
RE: BLE commands on nRF52840 - multiple reads and descriptor

If you only want to read one handle maybe consider using sd_ble_gattc_read() instead?

Kenneth

RE: Invalid parameter error returned on sd_ble_gattc_char_values_read()

TheThirdFriend — Tue, 06 Sep 2022 16:04:34 GMT

Yes, it returns 0x07 error code. I don't understand which parameter is invalid. could you please tell me how can I debug it?

RE: Invalid parameter error returned on sd_ble_gattc_char_values_read()

Kenneth — Tue, 06 Sep 2022 13:46:28 GMT

Are you sure that sd_ble_gattc_char_values_read() return 0x07? From nrf_error.h I can find that 0x07 means NRF_ERROR_INVALID_PARAM, though I can't find that specific error code listed in the api, but in any case the error code seems to give a hint that one of the parameters are invalid.

/**@brief Initiate a GATT Read Multiple Characteristic Values procedure.
 *
 * @details This function initiates a GATT Read Multiple Characteristic Values procedure.
 *
 * @events
 * @event{@ref BLE_GATTC_EVT_CHAR_VALS_READ_RSP}
 * @endevents
 *
 * @mscs
 * @mmsc{@ref BLE_GATTC_READ_MULT_MSC}
 * @endmscs
 *
 * @param[in] conn_handle The connection handle identifying the connection to perform this procedure on.
 * @param[in] p_handles A pointer to the handle(s) of the attribute(s) to be read.
 * @param[in] handle_count The number of handles in p_handles.
 *
 * @retval ::NRF_SUCCESS Successfully started the Read Multiple Characteristic Values procedure.
 * @retval ::BLE_ERROR_INVALID_CONN_HANDLE Invalid Connection Handle.
 * @retval ::NRF_ERROR_INVALID_STATE Invalid Connection State.
 * @retval ::NRF_ERROR_INVALID_ADDR Invalid pointer supplied.
 * @retval ::NRF_ERROR_BUSY Client procedure already in progress.
 * @retval ::NRF_ERROR_TIMEOUT There has been a GATT procedure timeout. No new GATT procedure can be performed without reestablishing the connection.
 */
SVCALL(SD_BLE_GATTC_CHAR_VALUES_READ, uint32_t, sd_ble_gattc_char_values_read(uint16_t conn_handle, uint16_t const *p_handles, uint16_t handle_count));

Best regards,
Kenneth