# SPDX-FileCopyrightText: 2017 Tony DiCola for Adafruit Industries
#
# SPDX-License-Identifier: MIT
"""
`adafruit_vl6180x`
====================================================
CircuitPython module for the VL6180X distance sensor. See
examples/simpletest.py for a demo of the usage.
* Author(s): Tony DiCola
Implementation Notes
--------------------
**Hardware:**
* Adafruit `VL6180X Time of Flight Distance Ranging Sensor (VL6180)
<https://www.adafruit.com/product/3316>`_ (Product ID: 3316)
**Software and Dependencies:**
* Adafruit CircuitPython firmware for the ESP8622 and M0-based boards:
https://github.com/adafruit/circuitpython/releases
* Adafruit's Bus Device library: https://github.com/adafruit/Adafruit_CircuitPython_BusDevice
"""
from micropython import const
import adafruit_bus_device.i2c_device as i2c_device
__version__ = "0.0.0-auto.0"
__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_VL6180X.git"
# Internal constants:
_VL6180X_DEFAULT_I2C_ADDR = const(0x29)
_VL6180X_REG_IDENTIFICATION_MODEL_ID = const(0x000)
_VL6180X_REG_SYSTEM_INTERRUPT_CONFIG = const(0x014)
_VL6180X_REG_SYSTEM_INTERRUPT_CLEAR = const(0x015)
_VL6180X_REG_SYSTEM_FRESH_OUT_OF_RESET = const(0x016)
_VL6180X_REG_SYSRANGE_START = const(0x018)
_VL6180X_REG_SYSALS_START = const(0x038)
_VL6180X_REG_SYSALS_ANALOGUE_GAIN = const(0x03F)
_VL6180X_REG_SYSALS_INTEGRATION_PERIOD_HI = const(0x040)
_VL6180X_REG_SYSALS_INTEGRATION_PERIOD_LO = const(0x041)
_VL6180X_REG_RESULT_ALS_VAL = const(0x050)
_VL6180X_REG_RESULT_RANGE_VAL = const(0x062)
_VL6180X_REG_RESULT_RANGE_STATUS = const(0x04D)
_VL6180X_REG_RESULT_INTERRUPT_STATUS_GPIO = const(0x04F)
# User-facing constants:
ALS_GAIN_1 = const(0x06)
ALS_GAIN_1_25 = const(0x05)
ALS_GAIN_1_67 = const(0x04)
ALS_GAIN_2_5 = const(0x03)
ALS_GAIN_5 = const(0x02)
ALS_GAIN_10 = const(0x01)
ALS_GAIN_20 = const(0x00)
ALS_GAIN_40 = const(0x07)
ERROR_NONE = const(0)
ERROR_SYSERR_1 = const(1)
ERROR_SYSERR_5 = const(5)
ERROR_ECEFAIL = const(6)
ERROR_NOCONVERGE = const(7)
ERROR_RANGEIGNORE = const(8)
ERROR_SNR = const(11)
ERROR_RAWUFLOW = const(12)
ERROR_RAWOFLOW = const(13)
ERROR_RANGEUFLOW = const(14)
ERROR_RANGEOFLOW = const(15)
[docs]class VL6180X:
"""Create an instance of the VL6180X distance sensor. You must pass in
the following parameters:
:param i2c: An instance of the I2C bus connected to the sensor.
Optionally you can specify:
:param address: The I2C address of the sensor. If not specified the sensor's
default value will be assumed.
"""
def __init__(self, i2c, address=_VL6180X_DEFAULT_I2C_ADDR):
self._device = i2c_device.I2CDevice(i2c, address)
if self._read_8(_VL6180X_REG_IDENTIFICATION_MODEL_ID) != 0xB4:
raise RuntimeError("Could not find VL6180X, is it connected and powered?")
self._load_settings()
self._write_8(_VL6180X_REG_SYSTEM_FRESH_OUT_OF_RESET, 0x00)
@property
def range(self):
"""Read the range of an object in front of sensor and return it in mm."""
# wait for device to be ready for range measurement
while not self._read_8(_VL6180X_REG_RESULT_RANGE_STATUS) & 0x01:
pass
# Start a range measurement
self._write_8(_VL6180X_REG_SYSRANGE_START, 0x01)
# Poll until bit 2 is set
while not self._read_8(_VL6180X_REG_RESULT_INTERRUPT_STATUS_GPIO) & 0x04:
pass
# read range in mm
range_ = self._read_8(_VL6180X_REG_RESULT_RANGE_VAL)
# clear interrupt
self._write_8(_VL6180X_REG_SYSTEM_INTERRUPT_CLEAR, 0x07)
return range_
[docs] def read_lux(self, gain):
"""Read the lux (light value) from the sensor and return it. Must
specify the gain value to use for the lux reading:
- ALS_GAIN_1 = 1x
- ALS_GAIN_1_25 = 1.25x
- ALS_GAIN_1_67 = 1.67x
- ALS_GAIN_2_5 = 2.5x
- ALS_GAIN_5 = 5x
- ALS_GAIN_10 = 10x
- ALS_GAIN_20 = 20x
- ALS_GAIN_40 = 40x
"""
reg = self._read_8(_VL6180X_REG_SYSTEM_INTERRUPT_CONFIG)
reg &= ~0x38
reg |= 0x4 << 3 # IRQ on ALS ready
self._write_8(_VL6180X_REG_SYSTEM_INTERRUPT_CONFIG, reg)
# 100 ms integration period
self._write_8(_VL6180X_REG_SYSALS_INTEGRATION_PERIOD_HI, 0)
self._write_8(_VL6180X_REG_SYSALS_INTEGRATION_PERIOD_LO, 100)
# analog gain
if gain > ALS_GAIN_40:
gain = ALS_GAIN_40
self._write_8(_VL6180X_REG_SYSALS_ANALOGUE_GAIN, 0x40 | gain)
# start ALS
self._write_8(_VL6180X_REG_SYSALS_START, 0x1)
# Poll until "New Sample Ready threshold event" is set
while (
(self._read_8(_VL6180X_REG_RESULT_INTERRUPT_STATUS_GPIO) >> 3) & 0x7
) != 4:
pass
# read lux!
lux = self._read_16(_VL6180X_REG_RESULT_ALS_VAL)
# clear interrupt
self._write_8(_VL6180X_REG_SYSTEM_INTERRUPT_CLEAR, 0x07)
lux *= 0.32 # calibrated count/lux
if gain == ALS_GAIN_1:
pass
elif gain == ALS_GAIN_1_25:
lux /= 1.25
elif gain == ALS_GAIN_1_67:
lux /= 1.67
elif gain == ALS_GAIN_2_5:
lux /= 2.5
elif gain == ALS_GAIN_5:
lux /= 5
elif gain == ALS_GAIN_10:
lux /= 10
elif gain == ALS_GAIN_20:
lux /= 20
elif gain == ALS_GAIN_40:
lux /= 40
lux *= 100
lux /= 100 # integration time in ms
return lux
@property
def range_status(self):
"""Retrieve the status/error from a previous range read. This will
return a constant value such as:
- ERROR_NONE - No error
- ERROR_SYSERR_1 - System error 1 (see datasheet)
- ERROR_SYSERR_5 - System error 5 (see datasheet)
- ERROR_ECEFAIL - ECE failure
- ERROR_NOCONVERGE - No convergence
- ERROR_RANGEIGNORE - Outside range ignored
- ERROR_SNR - Too much noise
- ERROR_RAWUFLOW - Raw value underflow
- ERROR_RAWOFLOW - Raw value overflow
- ERROR_RANGEUFLOW - Range underflow
- ERROR_RANGEOFLOW - Range overflow
"""
return self._read_8(_VL6180X_REG_RESULT_RANGE_STATUS) >> 4
def _load_settings(self):
# private settings from page 24 of app note
self._write_8(0x0207, 0x01)
self._write_8(0x0208, 0x01)
self._write_8(0x0096, 0x00)
self._write_8(0x0097, 0xFD)
self._write_8(0x00E3, 0x00)
self._write_8(0x00E4, 0x04)
self._write_8(0x00E5, 0x02)
self._write_8(0x00E6, 0x01)
self._write_8(0x00E7, 0x03)
self._write_8(0x00F5, 0x02)
self._write_8(0x00D9, 0x05)
self._write_8(0x00DB, 0xCE)
self._write_8(0x00DC, 0x03)
self._write_8(0x00DD, 0xF8)
self._write_8(0x009F, 0x00)
self._write_8(0x00A3, 0x3C)
self._write_8(0x00B7, 0x00)
self._write_8(0x00BB, 0x3C)
self._write_8(0x00B2, 0x09)
self._write_8(0x00CA, 0x09)
self._write_8(0x0198, 0x01)
self._write_8(0x01B0, 0x17)
self._write_8(0x01AD, 0x00)
self._write_8(0x00FF, 0x05)
self._write_8(0x0100, 0x05)
self._write_8(0x0199, 0x05)
self._write_8(0x01A6, 0x1B)
self._write_8(0x01AC, 0x3E)
self._write_8(0x01A7, 0x1F)
self._write_8(0x0030, 0x00)
# Recommended : Public registers - See data sheet for more detail
self._write_8(0x0011, 0x10) # Enables polling for 'New Sample ready'
# when measurement completes
self._write_8(0x010A, 0x30) # Set the averaging sample period
# (compromise between lower noise and
# increased execution time)
self._write_8(0x003F, 0x46) # Sets the light and dark gain (upper
# nibble). Dark gain should not be
# changed.
self._write_8(0x0031, 0xFF) # sets the # of range measurements after
# which auto calibration of system is
# performed
self._write_8(0x0040, 0x63) # Set ALS integration time to 100ms
self._write_8(0x002E, 0x01) # perform a single temperature calibration
# of the ranging sensor
# Optional: Public registers - See data sheet for more detail
self._write_8(0x001B, 0x09) # Set default ranging inter-measurement
# period to 100ms
self._write_8(0x003E, 0x31) # Set default ALS inter-measurement period
# to 500ms
self._write_8(0x0014, 0x24) # Configures interrupt on 'New Sample
# Ready threshold event'
def _write_8(self, address, data):
# Write 1 byte of data from the specified 16-bit register address.
with self._device:
self._device.write(bytes([(address >> 8) & 0xFF, address & 0xFF, data]))
def _write_16(self, address, data):
# Write a 16-bit big endian value to the specified 16-bit register
# address.
with self._device as i2c:
i2c.write(
bytes(
[
(address >> 8) & 0xFF,
address & 0xFF,
(data >> 8) & 0xFF,
data & 0xFF,
]
)
)
def _read_8(self, address):
# Read and return a byte from the specified 16-bit register address.
with self._device as i2c:
result = bytearray(1)
i2c.write(bytes([(address >> 8) & 0xFF, address & 0xFF]))
i2c.readinto(result)
return result[0]
def _read_16(self, address):
# Read and return a 16-bit unsigned big endian value read from the
# specified 16-bit register address.
with self._device as i2c:
result = bytearray(2)
i2c.write(bytes([(address >> 8) & 0xFF, address & 0xFF]))
i2c.readinto(result)
return (result[0] << 8) | result[1]