Hello!
I want to connect the MCP9808 with the nrf52832. Therefor I use i2C. My example on the nrf52832 is the:
<nRF5_SDK_v11_0_0 folder>\examples\ble_peripheral\experimental_ble_app_eddystone\
Now, I have written the code of the twi_sensor example in the eddystone example.
When I debug the program, the function err_code = nrf_drv_twi_rx(&m_twi_mcp9808, TEMP_ADDR, (uint8_t*)&m_sample, sizeof(m_sample)); in the void twi_handler(nrf_drv_twi_evt_t const * p_event, void * p_context) writes C1 in the MSB_Data and FF in the LSB_Data of the m_sample irrespective of the temperature.
Have I forgotten something in the program code.
My whole code:
/* Copyright (c) 2015 Nordic Semiconductor. All Rights Reserved.
*
* The information contained herein is property of Nordic Semiconductor ASA.
* Terms and conditions of usage are described in detail in NORDIC
* SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
*
* Licensees are granted free, non-transferable use of the information. NO
* WARRANTY of ANY KIND is provided. This heading must NOT be removed from
* the file.
*
*/
/** @file
*
* @defgroup experimental_ble_sdk_app_eddystone_main main.c
* @{
* @ingroup experimental_ble_sdk_app_eddystone
* @brief Eddystone Beacon UID Transmitter sample application main file.
*
* This file contains the source code for an Eddystone beacon transmitter sample application.
*/
#include <stdbool.h>
#include <stdint.h>
#include "ble_advdata.h"
#include "nordic_common.h"
#include "softdevice_handler.h"
#include "bsp.h"
#include "app_timer.h"
#include "nrf_temp.h" //XXX Neu
// XXX YYY Neu
#include "boards.h"
#include "app_util_platform.h"
#include "app_error.h"
#include "nrf_drv_twi.h"
#include "nrf_delay.h"
/*Pins to connect shield. */
#define DEVICE_SCL_PIN 0
#define DEVICE_SDA_PIN 1
/*Common addresses definition for accelereomter. */
#define TEMP_ADDR (0x18U)
#define TEMP_REG_RFU 0x00U
#define TEMP_REG_CONFIG 0x01U
#define TEMP_REG_TUPPER 0x02U
#define TEMP_REG_TLOWER 0x03U
#define TEMP_REG_TCRIT 0x04U
#define TEMP_REG_TEMP 0x05U
#define TEMP_REG_MID 0x06U
#define TEMP_REG_DID 0x07U
#define TEMP_REG_RESR 0x08U
// [max 255, otherwise "int16_t" won't be sufficient to hold the sum
// of accelerometer samples]
#define NUMBER_OF_SAMPLES 20
// XXX YYY Neu
#define IS_SRVC_CHANGED_CHARACT_PRESENT 0 /**< Include the service changed characteristic. If not enabled, the server's database cannot be changed for the lifetime of the device. */
#define CENTRAL_LINK_COUNT 0 /**< Number of central links used by the application. When changing this number remember to adjust the RAM settings*/
#define PERIPHERAL_LINK_COUNT 0 /**< Number of peripheral links used by the application. When changing this number remember to adjust the RAM settings*/
#define APP_CFG_NON_CONN_ADV_TIMEOUT 0 /**< Time for which the device must be advertising in non-connectable mode (in seconds). 0 disables the time-out. */
#define NON_CONNECTABLE_ADV_INTERVAL MSEC_TO_UNITS(1000, UNIT_0_625_MS) /**< The advertising interval for non-connectable advertisement (100 ms). This value can vary between 100 ms and 10.24 s). */
// Eddystone common data
#define APP_EDDYSTONE_UUID 0xFEAA /**< UUID for Eddystone beacons according to specification. */
#define APP_EDDYSTONE_RSSI 0xEE /**< 0xEE = -18 dB is the approximate signal strength at 0 m. */
// Eddystone UID data
#define APP_EDDYSTONE_UID_FRAME_TYPE 0x00 /**< UID frame type is fixed at 0x00. */
#define APP_EDDYSTONE_UID_RFU 0x00, 0x00 /**< Reserved for future use according to specification. */
#define APP_EDDYSTONE_UID_ID 0x01, 0x02, 0x03, 0x04, \
0x05, 0x06 /**< Mock values for 6-byte Eddystone UID ID instance. */
#define APP_EDDYSTONE_UID_NAMESPACE 0xAA, 0xAA, 0xBB, 0xBB, \
0xCC, 0xCC, 0xDD, 0xDD, \
0xEE, 0xEE /**< Mock values for 10-byte Eddystone UID ID namespace. */
// Eddystone URL data
#define APP_EDDYSTONE_URL_FRAME_TYPE 0x10 /**< URL Frame type is fixed at 0x10. */
#define APP_EDDYSTONE_URL_SCHEME 0x00 /**< 0x00 = "http://www" URL prefix scheme according to specification. */
#define APP_EDDYSTONE_URL_URL 0x6e, 0x6f, 0x72, 0x64, \
0x69, 0x63, 0x73, 0x65, \
0x6d,0x69, 0x00 /**< "nordicsemi.com". Last byte suffix 0x00 = ".com" according to specification. */
// Eddystone TLM data
#define APP_EDDYSTONE_TLM_FRAME_TYPE 0x20 /**< TLM frame type is fixed at 0x20. */
#define APP_EDDYSTONE_TLM_VERSION 0x00 /**< TLM version might change in the future to accommodate other data according to specification. */
#define APP_EDDYSTONE_TLM_BATTERY 0x00, 0xF0 /**< Mock value. Battery voltage in 1 mV per bit. */
#define APP_EDDYSTONE_TLM_TEMPERATURE 0x0F, 0x00 /**< Mock value. Temperature [C]. Signed 8.8 fixed-point notation. */
#define APP_EDDYSTONE_TLM_ADV_COUNT 0x00, 0x00, 0x00, 0x03 /**< Running count of advertisements of all types since power-up or reboot. */
#define APP_EDDYSTONE_TLM_SEC_COUNT 0x00, 0x00, 0x00, 0x04 /**< Running count in 0.1 s resolution since power-up or reboot. */
#define DEAD_BEEF 0xDEADBEEF /**< Value used as error code on stack dump, can be used to identify stack location on stack unwind. */
#define APP_TIMER_PRESCALER 0 /**< Value of the RTC1 PRESCALER register. */
#define APP_TIMER_OP_QUEUE_SIZE 4 /**< Size of timer operation queues. */
static ble_gap_adv_params_t m_adv_params; /**< Parameters to be passed to the stack when starting advertising. */
// XXX Neu
//static uint8_t eddystone_url_data[] = /**< Information advertised by the Eddystone URL frame type. */
//{
// APP_EDDYSTONE_URL_FRAME_TYPE, // Eddystone URL frame type.
// APP_EDDYSTONE_RSSI, // RSSI value at 0 m.
// APP_EDDYSTONE_URL_SCHEME, // Scheme or prefix for URL ("http", "http://www", etc.)
// APP_EDDYSTONE_URL_URL // URL with a maximum length of 17 bytes. Last byte is suffix (".com", ".org", etc.)
//};
/** @snippet [Eddystone UID data] */
//static uint8_t eddystone_uid_data[] = /**< Information advertised by the Eddystone UID frame type. */
//{
// APP_EDDYSTONE_UID_FRAME_TYPE, // Eddystone UID frame type.
// APP_EDDYSTONE_RSSI, // RSSI value at 0 m.
// APP_EDDYSTONE_UID_NAMESPACE, // 10-byte namespace value. Similar to Beacon Major.
// APP_EDDYSTONE_UID_ID, // 6-byte ID value. Similar to Beacon Minor.
// APP_EDDYSTONE_UID_RFU // Reserved for future use.
//};
/** @snippet [Eddystone UID data] */
// XXX Neu
static uint8_t eddystone_tlm_data[] = /**< Information advertised by the Eddystone TLM frame type. */
{
APP_EDDYSTONE_TLM_FRAME_TYPE, // Eddystone TLM frame type.
APP_EDDYSTONE_TLM_VERSION, // Eddystone TLM version.
APP_EDDYSTONE_TLM_BATTERY, // Battery voltage in mV/bit.
APP_EDDYSTONE_TLM_TEMPERATURE, // Temperature [C].
APP_EDDYSTONE_TLM_ADV_COUNT, // Number of advertisements since power-up or reboot.
APP_EDDYSTONE_TLM_SEC_COUNT // Time since power-up or reboot. 0.1 s increments.
};
// XXX YYY Neu
typedef struct
{
uint8_t MSB_Data;
uint8_t LSB_Data;
} sample_t;
sample_t Temp_Sensor;
/* Buffer for samples. */
static sample_t m_sample_buffer[NUMBER_OF_SAMPLES] = {0};
/* Indicates if reading operation from accelerometer has ended. */
static volatile bool m_xfer_done = true;
/* Indicates if setting mode operation has ended. */
static volatile bool m_set_mode_done = false;
/* TWI instance. */
static const nrf_drv_twi_t m_twi_mcp9808 = NRF_DRV_TWI_INSTANCE(0);
// XXX YYY Neu
/**@brief Callback function for asserts in the SoftDevice.
*
* @details This function will be called in case of an assert in the SoftDevice.
*
* @warning This handler is an example only and does not fit a final product. You need to analyze
* how your product is supposed to react in case of Assert.
* @warning On assert from the SoftDevice, the system can only recover on reset.
*
* @param[in] line_num Line number of the failing ASSERT call.
* @param[in] file_name File name of the failing ASSERT call.
*/
void assert_nrf_callback(uint16_t line_num, const uint8_t * p_file_name)
{
app_error_handler(DEAD_BEEF, line_num, p_file_name);
}
/**@brief Function for initializing the advertising functionality.
*
* @details Encodes the required advertising data and passes it to the stack.
* Also builds a structure to be passed to the stack when starting advertising.
*/
static void advertising_init(void)
{
uint32_t err_code;
int32_t temp;
uint8_t temp_a;
uint8_t temp_b;
ble_advdata_t advdata;
uint8_t flags = BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE;
ble_uuid_t adv_uuids[] = {{APP_EDDYSTONE_UUID, BLE_UUID_TYPE_BLE}};
uint8_array_t eddystone_data_array; // Array for Service Data structure.
/** @snippet [Eddystone data array] */
// XXX Neu
sd_temp_get(&temp);
temp_a = temp;
temp_b = temp;
temp_a >>= 2;
temp_b <<= 6;
eddystone_tlm_data [4] = temp_a;
eddystone_tlm_data [5] = temp_b;
eddystone_data_array.p_data = (uint8_t *) eddystone_tlm_data; // Pointer to the data to advertise.
eddystone_data_array.size = sizeof(eddystone_tlm_data); // Size of the data to advertise.
/** @snippet [Eddystone data array] */
ble_advdata_service_data_t service_data; // Structure to hold Service Data.
service_data.service_uuid = APP_EDDYSTONE_UUID; // Eddystone UUID to allow discoverability on iOS devices.
service_data.data = eddystone_data_array; // Array for service advertisement data.
// Build and set advertising data.
memset(&advdata, 0, sizeof(advdata));
advdata.name_type = BLE_ADVDATA_NO_NAME;
advdata.flags = flags;
advdata.uuids_complete.uuid_cnt = sizeof(adv_uuids) / sizeof(adv_uuids[0]);
advdata.uuids_complete.p_uuids = adv_uuids;
advdata.p_service_data_array = &service_data; // Pointer to Service Data structure.
advdata.service_data_count = 1;
err_code = ble_advdata_set(&advdata, NULL);
APP_ERROR_CHECK(err_code);
// Initialize advertising parameters (used when starting advertising).
memset(&m_adv_params, 0, sizeof(m_adv_params));
m_adv_params.type = BLE_GAP_ADV_TYPE_ADV_NONCONN_IND;
m_adv_params.p_peer_addr = NULL; // Undirected advertisement.
m_adv_params.fp = BLE_GAP_ADV_FP_ANY;
m_adv_params.interval = NON_CONNECTABLE_ADV_INTERVAL;
m_adv_params.timeout = APP_CFG_NON_CONN_ADV_TIMEOUT;
}
/**@brief Function for starting advertising.
*/
static void advertising_start(void)
{
uint32_t err_code;
err_code = sd_ble_gap_adv_start(&m_adv_params);
APP_ERROR_CHECK(err_code);
err_code = bsp_indication_set(BSP_INDICATE_ADVERTISING);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for initializing the BLE stack.
*
* @details Initializes the SoftDevice and the BLE event interrupt.
*/
static void ble_stack_init(void)
{
uint32_t err_code;
// XXX Neu
// see nrf_sdm.h for more details
nrf_clock_lf_cfg_t clock_lf_cfg =
{
.source = NRF_CLOCK_LF_SRC_RC,
.rc_ctiv = 16, // Interval in 0.25 s, 16 * 0.25 = 4 sec
.rc_temp_ctiv = 2, // Check temperature every .rc_ctiv, but calibrate every .rc_temp_ctiv
.xtal_accuracy = NRF_CLOCK_LF_XTAL_ACCURACY_250_PPM,
};
// Initialize the SoftDevice handler module.
SOFTDEVICE_HANDLER_INIT(&clock_lf_cfg, NULL);
ble_enable_params_t ble_enable_params;
err_code = softdevice_enable_get_default_config(CENTRAL_LINK_COUNT,
PERIPHERAL_LINK_COUNT,
&ble_enable_params);
APP_ERROR_CHECK(err_code);
//Check the ram settings against the used number of links
CHECK_RAM_START_ADDR(CENTRAL_LINK_COUNT,PERIPHERAL_LINK_COUNT);
// Enable BLE stack.
err_code = softdevice_enable(&ble_enable_params);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for doing power management.
*/
static void power_manage(void)
{
uint32_t err_code = sd_app_evt_wait();
APP_ERROR_CHECK(err_code);
}
/**
* @brief Function XXX YYY Neu for i2c.
*/
/**
* @brief Function for setting active mode on mcp9808.
*/
void mcp9808_set_mode(void)
{
ret_code_t err_code;
uint8_t reg[1] = {TEMP_REG_TEMP};
err_code = nrf_drv_twi_tx(&m_twi_mcp9808, TEMP_ADDR, reg, sizeof(reg), false);
APP_ERROR_CHECK(err_code);
while(m_set_mode_done == false);
}
/**
* @brief TWI events handler.
*/
void twi_handler(nrf_drv_twi_evt_t const * p_event, void * p_context)
{
ret_code_t err_code;
static sample_t m_sample;
switch(p_event->type)
{
case NRF_DRV_TWI_EVT_DONE:
if ((p_event->type == NRF_DRV_TWI_EVT_DONE) &&
(p_event->xfer_desc.type == NRF_DRV_TWI_XFER_TX))
{
if(m_set_mode_done != true)
{
m_set_mode_done = true;
return;
}
m_xfer_done = false;
/* Read 4 bytes from the specified address. */
err_code = nrf_drv_twi_rx(&m_twi_mcp9808, TEMP_ADDR, (uint8_t*)&m_sample, sizeof(m_sample));
APP_ERROR_CHECK(err_code);
}
else
{
Temp_Sensor = m_sample;
m_xfer_done = true;
}
break;
default:
break;
}
}
void twi_init (void)
{
ret_code_t err_code;
const nrf_drv_twi_config_t twi_mcp9808_config = {
.scl = DEVICE_SCL_PIN,
.sda = DEVICE_SDA_PIN,
.frequency = NRF_TWI_FREQ_100K,
.interrupt_priority = APP_IRQ_PRIORITY_HIGH
};
err_code = nrf_drv_twi_init(&m_twi_mcp9808, &twi_mcp9808_config, twi_handler, NULL);
APP_ERROR_CHECK(err_code);
nrf_drv_twi_enable(&m_twi_mcp9808);
}
// XXX YYY Neu
/**
* @brief Function for application main entry.
*/
int main(void)
{
uint32_t err_code;
uint32_t pin = 2;
nrf_gpio_cfg_output(pin);
nrf_gpio_pin_set(pin);
// Initialize.
APP_TIMER_INIT(APP_TIMER_PRESCALER, APP_TIMER_OP_QUEUE_SIZE, false);
err_code = bsp_init(BSP_INIT_LED, APP_TIMER_TICKS(100, APP_TIMER_PRESCALER), NULL);
// err_code = 0x0; //XXX Neu
APP_ERROR_CHECK(err_code);
ble_stack_init();
advertising_init();
twi_init();
mcp9808_set_mode();
// LEDS_ON(LEDS_MASK);
// Start execution.
advertising_start();
uint8_t reg = TEMP_REG_TEMP;
ret_code_t err_code_sens;
// Enter main loop.
for (;; )
{
nrf_delay_ms(100);
/* Start transaction with a slave with the specified address. */
do
{
__WFE();
}while(m_xfer_done == false);
err_code_sens = nrf_drv_twi_tx(&m_twi_mcp9808, TEMP_ADDR, ®, sizeof(reg), true);
APP_ERROR_CHECK(err_code_sens);
m_xfer_done = false;
power_manage();
advertising_init(); //XXX Neu
}
}
/**
* @}
*/
Thanks!
