Hi,
I am using the TWI scanner example from the sdk15. Board is NRF52840. I have a differential pressure sensor connected to the TWI input pins on the nordic board and am trying to read the pressure. However, for that I need to be able to observe that there is a device.
I have gotten this sensor working via an arduino with the same pin connections as I am using for the Nordic board. 2 4.7Kohm resistors one for each line upto VDD(3.3).
I am using the P27 and P26 ports as defined in the example they are not used for anything else. But when I run my terminal I just get a loop stating no devices are connected.
I can see using a logic analyser that the clock and data are running but no response. My sensor has the address of 0X40.
Here is my code:
/** * Copyright (c) 2016 - 2018, Nordic Semiconductor ASA * * All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, * are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * 2. Redistributions in binary form, except as embedded into a Nordic * Semiconductor ASA integrated circuit in a product or a software update for * such product, must reproduce the above copyright notice, this list of * conditions and the following disclaimer in the documentation and/or other * materials provided with the distribution. * * 3. Neither the name of Nordic Semiconductor ASA nor the names of its * contributors may be used to endorse or promote products derived from this * software without specific prior written permission. * * 4. This software, with or without modification, must only be used with a * Nordic Semiconductor ASA integrated circuit. * * 5. Any software provided in binary form under this license must not be reverse * engineered, decompiled, modified and/or disassembled. * * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ /** @file * @defgroup tw_scanner main.c * @{ * @ingroup nrf_twi_example * @brief TWI Sensor Example main file. * * This file contains the source code for a sample application using TWI. * */ #include <stdio.h> #include "boards.h" #include "app_util_platform.h" #include "app_error.h" #include "nrf_drv_twi.h" #include "nrf_delay.h" #include "nrf_log.h" #include "nrf_log_ctrl.h" #include "nrf_log_default_backends.h" /* TWI instance ID. */ #if TWI0_ENABLED #define TWI_INSTANCE_ID 0 #elif TWI1_ENABLED #define TWI_INSTANCE_ID 1 #endif /* Number of possible TWI addresses. */ #define TWI_ADDRESSES 127 /* TWI instance. */ static const nrf_drv_twi_t m_twi = NRF_DRV_TWI_INSTANCE(TWI_INSTANCE_ID); /** * @brief TWI initialization. */ void twi_init (void) { ret_code_t err_code; const nrf_drv_twi_config_t twi_config = { .scl = ARDUINO_SCL_PIN,//27 (green) .sda = ARDUINO_SDA_PIN,//26 (yellow) .frequency = NRF_DRV_TWI_FREQ_100K, .interrupt_priority = APP_IRQ_PRIORITY_HIGH, .clear_bus_init = false }; err_code = nrf_drv_twi_init(&m_twi, &twi_config, NULL, NULL); APP_ERROR_CHECK(err_code); nrf_drv_twi_enable(&m_twi); } /** * @brief Function for main application entry. */ int main(void) { ret_code_t err_code; uint8_t address; uint8_t sample_data; bool detected_device = false; APP_ERROR_CHECK(NRF_LOG_INIT(NULL)); NRF_LOG_DEFAULT_BACKENDS_INIT(); NRF_LOG_INFO("TWI scanner started."); NRF_LOG_FLUSH(); twi_init(); for (address = 1; address <= TWI_ADDRESSES; address++) { err_code = nrf_drv_twi_rx(&m_twi, address, &sample_data, sizeof(sample_data)); if (err_code == NRF_SUCCESS) { detected_device = true; NRF_LOG_INFO("TWI device detected at address 0x%x.", address); } NRF_LOG_FLUSH(); } if (!detected_device) { NRF_LOG_INFO("No device was found."); NRF_LOG_FLUSH(); } while (true) { for (address = 1; address <= TWI_ADDRESSES; address++) { err_code = nrf_drv_twi_rx(&m_twi, address, &sample_data, sizeof(sample_data)); if (err_code == NRF_SUCCESS) { detected_device = true; NRF_LOG_INFO("TWI device detected at address 0x%x.", address); } NRF_LOG_FLUSH(); } if (!detected_device) { NRF_LOG_INFO("No device was found."); NRF_LOG_FLUSH(); } nrf_delay_ms(500); } } /** @} */
Here is my scope:
Note the top line is the clock and bottom is the data (SCL and SDA respectively)
After fixing the issue of not seeing the device on the Nordic board I then will need to emulate my arduino code on the board to read this sensor.
Please could someone look into this issue
Thanks