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dieseltravis/Wire_nRF52.cpp

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Demo of using BMP280+AHT20 sensor on I2C with a Seeed Xiao nRF52840 Sense, and modifications to files in the Arduino packages to use different pins for SDA/SCL
Raw
aht-bmp-demo.ino
#include <Adafruit_AHTX0.h>
#include <Adafruit_BMP280.h>
Adafruit_AHTX0 aht;
Adafruit_BMP280 bmp;
void setup() {
unsigned status;
// Xiao nRF52840 specific pins:
pinMode(LED_RED, OUTPUT);
pinMode(LED_GREEN, OUTPUT);
pinMode(LED_BLUE, OUTPUT);
digitalWrite(LED_RED, LOW);
Serial.begin(9600);
delay(5000);
digitalWrite(LED_RED, HIGH);
// I can't figure out why serial printing doesn't work in setup
Serial.println("AHT20+BMP280 Demo");
digitalWrite(LED_GREEN, LOW);
status = aht.begin();
if (!status) {
Serial.println("Could not find AHT? Check wiring");
while (1) delay(10);
}
Serial.println("AHT10 or AHT20 found.");
digitalWrite(LED_GREEN, HIGH);
digitalWrite(LED_BLUE, LOW);
status = bmp.begin();
if (!status) {
Serial.println(F("Could not find a valid BMP280 sensor, check wiring or "
"try a different address!"));
Serial.print("SensorID was: 0x");
Serial.println(bmp.sensorID(), 16);
Serial.print(" ID of 0xFF probably means a bad address, a BMP 180 or BMP 085\n");
Serial.print(" ID of 0x56-0x58 represents a BMP 280,\n");
Serial.print(" ID of 0x60 represents a BME 280.\n");
Serial.print(" ID of 0x61 represents a BME 680.\n");
while (1) delay(10);
}
Serial.println("BMP280 found.");
digitalWrite(LED_BLUE, HIGH);
}
void loop() {
digitalWrite(LED_RED, LOW);
delay(500);
digitalWrite(LED_RED, HIGH);
delay(1000);
digitalWrite(LED_GREEN, LOW);
Serial.println("AHT20:");
sensors_event_t humidity, temp;
aht.getEvent(&humidity, &temp);// populate temp and humidity objects with fresh data
Serial.print("Temperature: ");
float aht_c = temp.temperature;
Serial.print(aht_c);
Serial.print("°C\t");
Serial.print(aht_c * 1.8 + 32);
Serial.println("°F");
Serial.print("Humidity: ");
Serial.print(humidity.relative_humidity);
Serial.println("% rH");
delay(1000);
digitalWrite(LED_GREEN, HIGH);
delay(1000);
Serial.println();
digitalWrite(LED_BLUE, LOW);
Serial.println("BMP280:");
Serial.print(F("Temperature: "));
float bmp_c = bmp.readTemperature();
Serial.print(bmp_c);
Serial.print("°C\t");
Serial.print(bmp_c * 1.8 + 32);
Serial.println("°F");
Serial.print(F("Pressure: "));
Serial.print(bmp.readPressure());
Serial.println(" Pa");
Serial.print(F("Approx altitude: "));
Serial.print(bmp.readAltitude(1013.25)); /* Adjusted to local forecast! */
Serial.println(" m");
delay(1000);
digitalWrite(LED_BLUE, HIGH);
Serial.println("\n");
delay(5000);
}
Raw
boards.txt
# C:\Users\travis\AppData\Local\Arduino15\packages\Seeeduino\hardware\nrf52\1.1.10\boards.txt
# ----------------------------------------^
# Add the block below to the boards.txt file to customize the SDA and SCL pins
# ----------------------------------
# Seeed XIAO nRF52840 Sense with SDA D6 & SCL D7
# ----------------------------------
xiaonRF52840SenseSDA6SCL7.name=Seeed XIAO nRF52840 Sense SDA6 SCL7
# VID/PID for bootloader
xiaonRF52840SenseSDA6SCL7.vid.0=0x2886
xiaonRF52840SenseSDA6SCL7.pid.0=0x8045
xiaonRF52840SenseSDA6SCL7.vid.1=0x2886
xiaonRF52840SenseSDA6SCL7.pid.1=0x0045
xiaonRF52840SenseSDA6SCL7.vid.2=0x2886
xiaonRF52840SenseSDA6SCL7.pid.2=0x0045
xiaonRF52840SenseSDA6SCL7.vid.3=0x2886
xiaonRF52840SenseSDA6SCL7.pid.3=0x8045
# Upload
xiaonRF52840SenseSDA6SCL7.bootloader.tool=bootburn
xiaonRF52840SenseSDA6SCL7.upload.tool=nrfutil
xiaonRF52840SenseSDA6SCL7.upload.protocol=nrfutil
xiaonRF52840SenseSDA6SCL7.upload.use_1200bps_touch=true
xiaonRF52840SenseSDA6SCL7.upload.wait_for_upload_port=true
xiaonRF52840SenseSDA6SCL7.upload.maximum_size=811008
xiaonRF52840SenseSDA6SCL7.upload.maximum_data_size=237568
# Build
xiaonRF52840SenseT.build.mcu=cortex-m4
xiaonRF52840SenseSDA6SCL7.build.f_cpu=64000000
xiaonRF52840SenseSDA6SCL7.build.board=Seeed_XIAO_nRF52840_Sense_SDA6SCL7
xiaonRF52840SenseSDA6SCL7.build.core=nRF5
xiaonRF52840SenseSDA6SCL7.build.variant=Seeed_XIAO_nRF52840_Sense_SDA6SCL7
xiaonRF52840SenseSDA6SCL7.build.usb_manufacturer="Seeed"
xiaonRF52840SenseSDA6SCL7.build.usb_product="XIAO nRF52840 Sense SDA6SCL7"
xiaonRF52840SenseSDA6SCL7.build.extra_flags=-DNRF52840_XXAA {build.flags.usb}
xiaonRF52840SenseSDA6SCL7.build.ldscript=nrf52840_s140_v7.ld
xiaonRF52840SenseSDA6SCL7.build.vid=0x2886
xiaonRF52840SenseSDA6SCL7.build.pid=0x8045
# SofDevice Menu
xiaonRF52840SenseSDA6SCL7.menu.softdevice.s140v6=S140 7.3.0
xiaonRF52840SenseSDA6SCL7.menu.softdevice.s140v6.build.sd_name=s140
xiaonRF52840SenseSDA6SCL7.menu.softdevice.s140v6.build.sd_version=7.3.0
xiaonRF52840SenseSDA6SCL7.menu.softdevice.s140v6.build.sd_fwid=0x0123
# Debug Menu
xiaonRF52840SenseSDA6SCL7.menu.debug.l0=Level 0 (Release)
xiaonRF52840SenseSDA6SCL7.menu.debug.l0.build.debug_flags=-DCFG_DEBUG=0
xiaonRF52840SenseSDA6SCL7.menu.debug.l1=Level 1 (Error Message)
xiaonRF52840SenseSDA6SCL7.menu.debug.l1.build.debug_flags=-DCFG_DEBUG=1
xiaonRF52840SenseSDA6SCL7.menu.debug.l2=Level 2 (Full Debug)
xiaonRF52840SenseSDA6SCL7.menu.debug.l2.build.debug_flags=-DCFG_DEBUG=2
xiaonRF52840SenseSDA6SCL7.menu.debug.l3=Level 3 (Segger SystemView)
xiaonRF52840SenseSDA6SCL7.menu.debug.l3.build.debug_flags=-DCFG_DEBUG=3
xiaonRF52840SenseSDA6SCL7.menu.debug.l3.build.sysview_flags=-DCFG_SYSVIEW=1
Raw
main.cpp
// C:\Users\travis\AppData\Local\Arduino15\packages\Seeeduino\hardware\nrf52\1.1.10\cores\nRF5\main.cpp
// ----------------------------------------^
// edit line # 55:
#if defined(ARDUINO_Seeed_XIAO_nRF52840) || defined(ARDUINO_Seeed_XIAO_nRF52840_Sense) || defined(ARDUINO_Seeed_XIAO_nRF52840_Sense_SDA6SCL7) || defined(ARDUINO_Seeed_XIAO_nRF52840_Plus) || defined(ARDUINO_Seeed_XIAO_nRF52840_Sense_Plus)
Raw
variant.cpp
// C:\Users\travis\AppData\Local\Arduino15\packages\Seeeduino\hardware\nrf52\1.1.10\variants\Seeed_XIAO_nRF52840_Sense_SDA6SCL7\variant.cpp
// ----------------------------------------^ ^
// ------------------------------------------------------------------------------------------| New Folder
#include "variant.h"
#include "wiring_constants.h"
#include "wiring_digital.h"
#include "nrf.h"
const uint32_t g_ADigitalPinMap[] =
{
// D0 .. D10
2, // D0 is P0.02 (A0)
3, // D1 is P0.03 (A1)
28, // D2 is P0.28 (A2)
29, // D3 is P0.29 (A3)
4, // D4 is P0.04 (A4)
5, // D5 is P0.05 (A5)
43, // D6 is P1.11 (TX,SDA)
44, // D7 is P1.12 (RX,SCL)
45, // D8 is P1.13 (SCK)
46, // D9 is P1.14 (MISO)
47, // D10 is P1.15 (MOSI)
// LEDs
26, // D11 is P0.26 (LED RED)
6, // D12 is P0.06 (LED BLUE)
30, // D13 is P0.30 (LED GREEN)
14, // D14 is P0.14 (READ_BAT)
// LSM6DS3TR
40, // D15 is P1.08 (6D_PWR)
27, // D16 is P0.27 (6D_I2C_SCL)
7, // D17 is P0.07 (6D_I2C_SDA)
11, // D18 is P0.11 (6D_INT1)
// MIC
42, // D19 is P1.10 (MIC_PWR)
32, // D20 is P1.00 (PDM_CLK)
16, // D21 is P0.16 (PDM_DATA)
// BQ25100
13, // D22 is P0.13 (HICHG)
17, // D23 is P0.17 (~CHG)
//
21, // D24 is P0.21 (QSPI_SCK)
25, // D25 is P0.25 (QSPI_CSN)
20, // D26 is P0.20 (QSPI_SIO_0 DI)
24, // D27 is P0.24 (QSPI_SIO_1 DO)
22, // D28 is P0.22 (QSPI_SIO_2 WP)
23, // D29 is P0.23 (QSPI_SIO_3 HOLD)
// NFC
9, // D30 is P0.09 (NFC1)
10, // D31 is P0.10 (NFC2)
// VBAT
31, // D32 is P0.31 (VBAT)
};
void initVariant()
{
// Disable reading of the BAT voltage.
// https://wiki.seeedstudio.com/XIAO_BLE#q3-what-are-the-considerations-when-using-xiao-nrf52840-sense-for-battery-charging
pinMode(VBAT_ENABLE, OUTPUT);
digitalWrite(VBAT_ENABLE, HIGH);
// Low charging current.
// https://wiki.seeedstudio.com/XIAO_BLE#battery-charging-current
pinMode(PIN_CHARGING_CURRENT, INPUT);
pinMode(PIN_QSPI_CS, OUTPUT);
digitalWrite(PIN_QSPI_CS, HIGH);
pinMode(LED_RED, OUTPUT);
digitalWrite(LED_RED, HIGH);
pinMode(LED_GREEN, OUTPUT);
digitalWrite(LED_GREEN, HIGH);
pinMode(LED_BLUE, OUTPUT);
digitalWrite(LED_BLUE, HIGH);
}
Raw
variant.h
// C:\Users\travis\AppData\Local\Arduino15\packages\Seeeduino\hardware\nrf52\1.1.10\variants\Seeed_XIAO_nRF52840_Sense_SDA6SCL7\variant.h
// ----------------------------------------^ ^
// ------------------------------------------------------------------------------------------| New Folder
#ifndef _SEEED_XIAO_NRF52840_SENSE_H_
#define _SEEED_XIAO_NRF52840_SENSE_H_
#define TARGET_SEEED_XIAO_NRF52840_SENSE
#define TARGET_SEEED_XIAO_NRF52840_SENSE_SDA6SCL7
/** Master clock frequency */
#define VARIANT_MCK (64000000ul)
#define USE_LFXO // Board uses 32khz crystal for LF
//#define USE_LFRC // Board uses RC for LF
/*----------------------------------------------------------------------------
* Headers
*----------------------------------------------------------------------------*/
#include "WVariant.h"
#ifdef __cplusplus
extern "C"
{
#endif // __cplusplus
#define PINS_COUNT (33)
#define NUM_DIGITAL_PINS (33)
#define NUM_ANALOG_INPUTS (8)
#define NUM_ANALOG_OUTPUTS (0)
// LEDs
#define PIN_LED (LED_RED)
#define LED_PWR (PINS_COUNT)
#define PIN_NEOPIXEL (PINS_COUNT)
#define NEOPIXEL_NUM (0)
#define LED_BUILTIN (PIN_LED)
#define LED_RED (11)
#define LED_GREEN (13)
#define LED_BLUE (12)
#define LED_STATE_ON (1) // State when LED is litted
// Buttons
#define PIN_BUTTON1 (PINS_COUNT)
// Digital PINs
static const uint8_t D0 = 0 ;
static const uint8_t D1 = 1 ;
static const uint8_t D2 = 2 ;
static const uint8_t D3 = 3 ;
static const uint8_t D4 = 4 ;
static const uint8_t D5 = 5 ;
static const uint8_t D6 = 6 ;
static const uint8_t D7 = 7 ;
static const uint8_t D8 = 8 ;
static const uint8_t D9 = 9 ;
static const uint8_t D10 = 10;
#define VBAT_ENABLE (14) // Output LOW to enable reading of the BAT voltage.
// https://wiki.seeedstudio.com/XIAO_BLE#q3-what-are-the-considerations-when-using-xiao-nrf52840-sense-for-battery-charging
#define PIN_CHARGING_CURRENT (22) // Battery Charging current
// https://wiki.seeedstudio.com/XIAO_BLE#battery-charging-current
// Analog pins
#define PIN_A0 (0)
#define PIN_A1 (1)
#define PIN_A2 (2)
#define PIN_A3 (3)
#define PIN_A4 (4)
#define PIN_A5 (5)
#define PIN_VBAT (32) // Read the BAT voltage.
// https://wiki.seeedstudio.com/XIAO_BLE#q3-what-are-the-considerations-when-using-xiao-nrf52840-sense-for-battery-charging
static const uint8_t A0 = PIN_A0;
static const uint8_t A1 = PIN_A1;
static const uint8_t A2 = PIN_A2;
static const uint8_t A3 = PIN_A3;
static const uint8_t A4 = PIN_A4;
static const uint8_t A5 = PIN_A5;
#define ADC_RESOLUTION (12)
// Other pins
#define PIN_NFC1 (30)
#define PIN_NFC2 (31)
// Serial interfaces
#define PIN_SERIAL1_RX (7)
#define PIN_SERIAL1_TX (6)
// SPI Interfaces
#define SPI_INTERFACES_COUNT (2)
#define PIN_SPI_MISO (9)
#define PIN_SPI_MOSI (10)
#define PIN_SPI_SCK (8)
static const uint8_t SS = 7;
static const uint8_t MOSI = PIN_SPI_MOSI;
static const uint8_t MISO = PIN_SPI_MISO;
static const uint8_t SCK = PIN_SPI_SCK ;
#define PIN_SPI1_MISO (25)
#define PIN_SPI1_MOSI (26)
#define PIN_SPI1_SCK (29)
// Wire Interfaces
#define WIRE_INTERFACES_COUNT (2)
// Redefining SDA and SCL here:
#define PIN_WIRE_SDA (6)
#define PIN_WIRE_SCL (7)
static const uint8_t SDA = PIN_WIRE_SDA;
static const uint8_t SCL = PIN_WIRE_SCL;
#define PIN_WIRE1_SDA (17)
#define PIN_WIRE1_SCL (16)
#define PIN_LSM6DS3TR_C_POWER (15)
#define PIN_LSM6DS3TR_C_INT1 (18)
// PDM Interfaces
#define PIN_PDM_PWR (19)
#define PIN_PDM_CLK (20)
#define PIN_PDM_DIN (21)
// QSPI Pins
#define PIN_QSPI_SCK (24)
#define PIN_QSPI_CS (25)
#define PIN_QSPI_IO0 (26)
#define PIN_QSPI_IO1 (27)
#define PIN_QSPI_IO2 (28)
#define PIN_QSPI_IO3 (29)
// On-board QSPI Flash
#define EXTERNAL_FLASH_DEVICES (P25Q16H)
#define EXTERNAL_FLASH_USE_QSPI
#ifdef __cplusplus
}
#endif
/*----------------------------------------------------------------------------
* Arduino objects - C++ only
*----------------------------------------------------------------------------*/
#endif
Raw
Wire_nRF52.cpp
// C:\Users\travis\AppData\Local\Arduino15\packages\Seeeduino\hardware\nrf52\1.1.10\libraries\Wire\Wire_nRF52.cpp
// ----------------------------------------^
// Edit line # 32
#if defined(ARDUINO_Seeed_XIAO_nRF52840) || defined(ARDUINO_Seeed_XIAO_nRF52840_Sense) || defined(ARDUINO_Seeed_XIAO_nRF52840_Sense_SDA6SCL7) || defined(ARDUINO_Seeed_XIAO_nRF52840_Plus) || defined(ARDUINO_Seeed_XIAO_nRF52840_Sense_Plus) || defined(ARDUINO_TRACKER_T1000_E_LORAWAN)
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