6e647c6f26
adc/microphone_adc - Read analog values from a microphone and plot the measured sound amplitude. i2c/bmp280_i2c - Read and convert temperature and pressure data from a BMP280 sensor, attached to an I2C bus. i2c/lis3dh_i2c - Read acceleration and temperature value from a LIS3DH sensor via I2C i2c/mcp9808_i2c - Read temperature, set limits and raise alerts when limits are surpassed. i2c/mma8451_i2c - Read acceleration from a MMA8451 accelerometer and set range and precision for the data. i2c/mpl3115a2_i2c - Interface with an MPL3115A2 altimeter, exploring interrupts and advanced board features, via I2C. i2c/oled_i2c - Convert and display a bitmap on a 128x32 SSD1306-driven OLED display i2c/pa1010d_i2c - Read GPS location data, parse and display data via I2C. i2c/pcf8523_i2c - Read time and date values from a real time clock. Set current time and alarms on it. uart/lcd_uart - Display text and symbols on a 16x02 RGB LCD display via UART
130 lines
3.9 KiB
C
130 lines
3.9 KiB
C
/**
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* Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
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*
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* SPDX-License-Identifier: BSD-3-Clause
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*/
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#include <stdio.h>
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#include <string.h>
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#include "pico/stdlib.h"
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#include "pico/binary_info.h"
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#include "hardware/i2c.h"
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/* Example code to talk to a LIS3DH Mini GPS module.
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This example reads data from all 3 axes of the accelerometer and uses an auxillary ADC to output temperature values.
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Connections on Raspberry Pi Pico board, other boards may vary.
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GPIO PICO_DEFAULT_I2C_SDA_PIN (On Pico this is 4 (physical pin 6)) -> SDA on LIS3DH board
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GPIO PICO_DEFAULT_I2C_SCK_PIN (On Pico this is 5 (physical pin 7)) -> SCL on LIS3DH board
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3.3v (physical pin 36) -> VIN on LIS3DH board
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GND (physical pin 38) -> GND on LIS3DH board
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*/
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// By default this device is on bus address 0x18
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const int ADDRESS = 0x18;
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const uint8_t CTRL_REG_1 = 0x20;
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const uint8_t CTRL_REG_4 = 0x23;
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const uint8_t TEMP_CFG_REG = 0xC0;
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#ifdef i2c_default
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void lis3dh_init() {
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uint8_t buf[2];
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// Turn normal mode and 1.344kHz data rate on
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buf[0] = CTRL_REG_1;
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buf[1] = 0x97;
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i2c_write_blocking(i2c_default, ADDRESS, buf, 2, false);
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// Turn block data update on (for temperature sensing)
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buf[0] = CTRL_REG_4;
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buf[1] = 0x80;
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i2c_write_blocking(i2c_default, ADDRESS, buf, 2, false);
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// Turn auxillary ADC on
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buf[0] = TEMP_CFG_REG;
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buf[1] = 0xC0;
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i2c_write_blocking(i2c_default, ADDRESS, buf, 2, false);
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}
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void lis3dh_calc_value(uint16_t raw_value, float *final_value, bool isAccel) {
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// Convert with respect to the value being temperature or acceleration reading
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float scaling;
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float senstivity = 0.004f; // g per unit
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if (isAccel == true) {
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scaling = 64 / senstivity;
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} else {
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scaling = 64;
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}
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// raw_value is signed
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*final_value = (float) ((int16_t) raw_value) / scaling;
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}
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void lis3dh_read_data(uint8_t reg, float *final_value, bool IsAccel) {
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// Read two bytes of data and store in a 16 bit data structure
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uint8_t lsb;
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uint8_t msb;
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uint16_t raw_accel;
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i2c_write_blocking(i2c_default, ADDRESS, ®, 1, true);
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i2c_read_blocking(i2c_default, ADDRESS, &lsb, 1, false);
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reg |= 0x01;
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i2c_write_blocking(i2c_default, ADDRESS, ®, 1, true);
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i2c_read_blocking(i2c_default, ADDRESS, &msb, 1, false);
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raw_accel = (msb << 8) | lsb;
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lis3dh_calc_value(raw_accel, final_value, IsAccel);
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}
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#endif
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int main() {
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stdio_init_all();
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#if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
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#warning i2c/lis3dh_i2c example requires a board with I2C pins
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puts("Default I2C pins were not defined");
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#else
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printf("Hello, LIS3DH! Reading raw data from registers...\n");
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// This example will use I2C0 on the default SDA and SCL pins (4, 5 on a Pico)
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i2c_init(i2c_default, 400 * 1000);
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gpio_set_function(PICO_DEFAULT_I2C_SDA_PIN, GPIO_FUNC_I2C);
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gpio_set_function(PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C);
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gpio_pull_up(PICO_DEFAULT_I2C_SDA_PIN);
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gpio_pull_up(PICO_DEFAULT_I2C_SCL_PIN);
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// Make the I2C pins available to picotool
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bi_decl(bi_2pins_with_func(PICO_DEFAULT_I2C_SDA_PIN, PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C));
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float x_accel, y_accel, z_accel, temp;
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lis3dh_init();
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while (1) {
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lis3dh_read_data(0x28, &x_accel, true);
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lis3dh_read_data(0x2A, &y_accel, true);
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lis3dh_read_data(0x2C, &z_accel, true);
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lis3dh_read_data(0x0C, &temp, false);
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// Display data
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printf("TEMPERATURE: %.3f%cC\n", temp, 176);
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// Acceleration is read as a multiple of g (gravitational acceleration on the Earth's surface)
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printf("ACCELERATION VALUES: \n");
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printf("X acceleration: %.3fg\n", x_accel);
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printf("Y acceleration: %.3fg\n", y_accel);
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printf("Z acceleration: %.3fg\n", z_accel);
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sleep_ms(500);
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// Clear terminal
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printf("\e[1;1H\e[2J");
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}
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#endif
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return 0;
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}
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