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// ADXL345 3-Axis Accelerometer - Arduino I2C Example
// Library: Adafruit ADXL345 (install via Library Manager)
// Wiring: SDA -> A4, SCL -> A5, 5V -> 5V, GND -> GND, CS -> 3.3V

#include 
#include 
#include 

Adafruit_ADXL345_Unified accel = Adafruit_ADXL345_Unified(12345);

void setup() {
  Serial.begin(9600);
  Serial.println("ADXL345 starting...");

  if (!accel.begin()) {
    Serial.println("No ADXL345 detected. Check wiring and CS pin.");
    while (1);
  }

  accel.setRange(ADXL345_RANGE_4_G);
  Serial.println("ADXL345 ready.");
}

void loop() {
  sensors_event_t event;
  accel.getEvent(&event);

  Serial.print("X: "); Serial.print(event.acceleration.x); Serial.print(" m/s^2  ");
  Serial.print("Y: "); Serial.print(event.acceleration.y); Serial.print(" m/s^2  ");
  Serial.print("Z: "); Serial.print(event.acceleration.z); Serial.println(" m/s^2");

  delay(200);
}

#!/usr/bin/env python3
# ADXL345 - Raspberry Pi I2C Example
# Install: sudo apt install python3-smbus
# Wiring: SDA -> GPIO 2, SCL -> GPIO 3, 3V3 -> 3.3V, GND -> GND, CS -> 3.3V

import smbus2
import time

ADDR = 0x53          # default I2C address
POWER_CTL = 0x2D
DATA_FORMAT = 0x31
DATAX0 = 0x32
SCALE = 0.0039 * 9.80665  # +/-2g, full-res: 3.9 mg/LSB -> m/s^2

bus = smbus2.SMBus(1)

def setup():
    bus.write_byte_data(ADDR, DATA_FORMAT, 0x08)  # full-res, +/-2g
    bus.write_byte_data(ADDR, POWER_CTL, 0x08)    # measurement mode

def read_axes():
    raw = bus.read_i2c_block_data(ADDR, DATAX0, 6)
    x = int.from_bytes(raw[0:2], 'little', signed=True) * SCALE
    y = int.from_bytes(raw[2:4], 'little', signed=True) * SCALE
    z = int.from_bytes(raw[4:6], 'little', signed=True) * SCALE
    return x, y, z

setup()
try:
    while True:
        x, y, z = read_axes()
        print("X: {:6.2f}  Y: {:6.2f}  Z: {:6.2f}  m/s^2".format(x, y, z))
        time.sleep(0.2)
except KeyboardInterrupt:
    print("Stopped by user")

# ADXL345 - Raspberry Pi Pico MicroPython Example
# Wiring: SDA -> GP4, SCL -> GP5, 3V3 -> 3V3 OUT, GND -> GND, CS -> 3V3

from machine import I2C, Pin
import time

ADDR = 0x53
POWER_CTL = 0x2D
DATA_FORMAT = 0x31
DATAX0 = 0x32
SCALE = 0.0039 * 9.80665  # +/-2g, full-res

i2c = I2C(0, sda=Pin(4), scl=Pin(5), freq=400000)

# Configure: full-res, +/-2g, then enable measurement mode
i2c.writeto_mem(ADDR, DATA_FORMAT, b'\x08')
i2c.writeto_mem(ADDR, POWER_CTL, b'\x08')

while True:
    raw = i2c.readfrom_mem(ADDR, DATAX0, 6)
    x = int.from_bytes(raw[0:2], 'little')
    y = int.from_bytes(raw[2:4], 'little')
    z = int.from_bytes(raw[4:6], 'little')
    # Convert unsigned to signed 16-bit
    if x > 32767: x -= 65536
    if y > 32767: y -= 65536
    if z > 32767: z -= 65536
    print("X: {:6.2f}  Y: {:6.2f}  Z: {:6.2f}  m/s^2".format(
        x * SCALE, y * SCALE, z * SCALE))
    time.sleep(0.2)

# ADXL345 - ESP32 MicroPython Example
# Wiring: SDA -> GPIO 21, SCL -> GPIO 22, 3V3 -> 3.3V, GND -> GND, CS -> 3.3V

from machine import I2C, Pin
import time

ADDR = 0x53
POWER_CTL = 0x2D
DATA_FORMAT = 0x31
DATAX0 = 0x32
SCALE = 0.0039 * 9.80665

i2c = I2C(0, sda=Pin(21), scl=Pin(22), freq=400000)

i2c.writeto_mem(ADDR, DATA_FORMAT, b'\x08')  # full-res, +/-2g
i2c.writeto_mem(ADDR, POWER_CTL, b'\x08')    # measurement mode

while True:
    raw = i2c.readfrom_mem(ADDR, DATAX0, 6)
    x = int.from_bytes(raw[0:2], 'little')
    y = int.from_bytes(raw[2:4], 'little')
    z = int.from_bytes(raw[4:6], 'little')
    if x > 32767: x -= 65536
    if y > 32767: y -= 65536
    if z > 32767: z -= 65536
    print("X: {:6.2f}  Y: {:6.2f}  Z: {:6.2f}  m/s^2".format(
        x * SCALE, y * SCALE, z * SCALE))
    time.sleep(0.2)