545 lines
22 KiB
Python
545 lines
22 KiB
Python
# SPDX-FileCopyrightText: 2017 Tony DiCola for Adafruit Industries
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# SPDX-License-Identifier: MIT
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#
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# Modified by Kevin Zhu to work on the ESP32 running Micropython 1.14
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# Modified by Salvatore Sanfilippo for non-blocking API.
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#
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# This code is released under the MIT license.
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import math
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import utime
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__version__ = "0.0.0-auto.0"
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__repo__ = "https://github.com/antirez/VL53L0X.git"
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# Configuration constants:
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_SYSRANGE_START = const(0x00)
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_SYSTEM_THRESH_HIGH = const(0x0C)
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_SYSTEM_THRESH_LOW = const(0x0E)
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_SYSTEM_SEQUENCE_CONFIG = const(0x01)
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_SYSTEM_RANGE_CONFIG = const(0x09)
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_SYSTEM_INTERMEASUREMENT_PERIOD = const(0x04)
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_SYSTEM_INTERRUPT_CONFIG_GPIO = const(0x0A)
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_GPIO_HV_MUX_ACTIVE_HIGH = const(0x84)
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_SYSTEM_INTERRUPT_CLEAR = const(0x0B)
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_RESULT_INTERRUPT_STATUS = const(0x13)
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_RESULT_RANGE_STATUS = const(0x14)
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_RESULT_CORE_AMBIENT_WINDOW_EVENTS_RTN = const(0xBC)
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_RESULT_CORE_RANGING_TOTAL_EVENTS_RTN = const(0xC0)
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_RESULT_CORE_AMBIENT_WINDOW_EVENTS_REF = const(0xD0)
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_RESULT_CORE_RANGING_TOTAL_EVENTS_REF = const(0xD4)
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_RESULT_PEAK_SIGNAL_RATE_REF = const(0xB6)
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_ALGO_PART_TO_PART_RANGE_OFFSET_MM = const(0x28)
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_I2C_SLAVE_DEVICE_ADDRESS = const(0x8A)
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_MSRC_CONFIG_CONTROL = const(0x60)
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_PRE_RANGE_CONFIG_MIN_SNR = const(0x27)
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_PRE_RANGE_CONFIG_VALID_PHASE_LOW = const(0x56)
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_PRE_RANGE_CONFIG_VALID_PHASE_HIGH = const(0x57)
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_PRE_RANGE_MIN_COUNT_RATE_RTN_LIMIT = const(0x64)
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_FINAL_RANGE_CONFIG_MIN_SNR = const(0x67)
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_FINAL_RANGE_CONFIG_VALID_PHASE_LOW = const(0x47)
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_FINAL_RANGE_CONFIG_VALID_PHASE_HIGH = const(0x48)
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_FINAL_RANGE_CONFIG_MIN_COUNT_RATE_RTN_LIMIT = const(0x44)
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_PRE_RANGE_CONFIG_SIGMA_THRESH_HI = const(0x61)
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_PRE_RANGE_CONFIG_SIGMA_THRESH_LO = const(0x62)
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_PRE_RANGE_CONFIG_VCSEL_PERIOD = const(0x50)
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_PRE_RANGE_CONFIG_TIMEOUT_MACROP_HI = const(0x51)
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_PRE_RANGE_CONFIG_TIMEOUT_MACROP_LO = const(0x52)
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_SYSTEM_HISTOGRAM_BIN = const(0x81)
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_HISTOGRAM_CONFIG_INITIAL_PHASE_SELECT = const(0x33)
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_HISTOGRAM_CONFIG_READOUT_CTRL = const(0x55)
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_FINAL_RANGE_CONFIG_VCSEL_PERIOD = const(0x70)
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_FINAL_RANGE_CONFIG_TIMEOUT_MACROP_HI = const(0x71)
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_FINAL_RANGE_CONFIG_TIMEOUT_MACROP_LO = const(0x72)
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_CROSSTALK_COMPENSATION_PEAK_RATE_MCPS = const(0x20)
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_MSRC_CONFIG_TIMEOUT_MACROP = const(0x46)
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_SOFT_RESET_GO2_SOFT_RESET_N = const(0xBF)
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_IDENTIFICATION_MODEL_ID = const(0xC0)
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_IDENTIFICATION_REVISION_ID = const(0xC2)
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_OSC_CALIBRATE_VAL = const(0xF8)
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_GLOBAL_CONFIG_VCSEL_WIDTH = const(0x32)
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_GLOBAL_CONFIG_SPAD_ENABLES_REF_0 = const(0xB0)
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_GLOBAL_CONFIG_SPAD_ENABLES_REF_1 = const(0xB1)
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_GLOBAL_CONFIG_SPAD_ENABLES_REF_2 = const(0xB2)
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_GLOBAL_CONFIG_SPAD_ENABLES_REF_3 = const(0xB3)
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_GLOBAL_CONFIG_SPAD_ENABLES_REF_4 = const(0xB4)
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_GLOBAL_CONFIG_SPAD_ENABLES_REF_5 = const(0xB5)
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_GLOBAL_CONFIG_REF_EN_START_SELECT = const(0xB6)
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_DYNAMIC_SPAD_NUM_REQUESTED_REF_SPAD = const(0x4E)
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_DYNAMIC_SPAD_REF_EN_START_OFFSET = const(0x4F)
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_POWER_MANAGEMENT_GO1_POWER_FORCE = const(0x80)
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_VHV_CONFIG_PAD_SCL_SDA__EXTSUP_HV = const(0x89)
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_ALGO_PHASECAL_LIM = const(0x30)
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_ALGO_PHASECAL_CONFIG_TIMEOUT = const(0x30)
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_VCSEL_PERIOD_PRE_RANGE = const(0)
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_VCSEL_PERIOD_FINAL_RANGE = const(1)
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def _decode_timeout(val):
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# format: "(LSByte * 2^MSByte) + 1"
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return float(val & 0xFF) * math.pow(2.0, ((val & 0xFF00) >> 8)) + 1
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def _encode_timeout(timeout_mclks):
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# format: "(LSByte * 2^MSByte) + 1"
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timeout_mclks = int(timeout_mclks) & 0xFFFF
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ls_byte = 0
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ms_byte = 0
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if timeout_mclks > 0:
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ls_byte = timeout_mclks - 1
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while ls_byte > 255:
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ls_byte >>= 1
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ms_byte += 1
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return ((ms_byte << 8) | (ls_byte & 0xFF)) & 0xFFFF
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return 0
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def _timeout_mclks_to_microseconds(timeout_period_mclks, vcsel_period_pclks):
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macro_period_ns = ((2304 * (vcsel_period_pclks) * 1655) + 500) // 1000
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return ((timeout_period_mclks * macro_period_ns) + (macro_period_ns // 2)) // 1000
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def _timeout_microseconds_to_mclks(timeout_period_us, vcsel_period_pclks):
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macro_period_ns = ((2304 * (vcsel_period_pclks) * 1655) + 500) // 1000
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return ((timeout_period_us * 1000) + (macro_period_ns // 2)) // macro_period_ns
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class VL53L0X:
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"""Driver for the VL53L0X distance sensor."""
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# Class-level buffer for reading and writing data with the sensor.
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# This reduces memory allocations but means the code is not re-entrant or
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# thread safe!
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_BUFFER = bytearray(3)
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def __init__(self, i2c, address=41, io_timeout_s=0):
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# pylint: disable=too-many-statements
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self._i2c = i2c
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self.address = address
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self.io_timeout_s = io_timeout_s
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self.range_started = False # True if a measure was initiated.
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# Check identification registers for expected values.
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# From section 3.2 of the datasheet.
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if (
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self._read_u8(0xC0) != 0xEE
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or self._read_u8(0xC1) != 0xAA
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or self._read_u8(0xC2) != 0x10
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):
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raise RuntimeError(
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"Failed to find expected ID register values. Check wiring! C0,C1,C2:", self._i2c.readfrom_mem(self.address, 0xc0, 3)
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)
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# Initialize access to the sensor. This is based on the logic from:
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# https://github.com/pololu/vl53l0x-arduino/blob/master/VL53L0X.cpp
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# Set I2C standard mode.
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for pair in ((0x88, 0x00), (0x80, 0x01), (0xFF, 0x01), (0x00, 0x00)):
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self._write_u8(pair[0], pair[1])
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self._stop_variable = self._read_u8(0x91)
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for pair in ((0x00, 0x01), (0xFF, 0x00), (0x80, 0x00)):
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self._write_u8(pair[0], pair[1])
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# disable SIGNAL_RATE_MSRC (bit 1) and SIGNAL_RATE_PRE_RANGE (bit 4)
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# limit checks
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config_control = self._read_u8(_MSRC_CONFIG_CONTROL) | 0x12
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self._write_u8(_MSRC_CONFIG_CONTROL, config_control)
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# set final range signal rate limit to 0.25 MCPS (million counts per
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# second)
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self.signal_rate_limit = 0.25
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self._write_u8(_SYSTEM_SEQUENCE_CONFIG, 0xFF)
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spad_count, spad_is_aperture = self._get_spad_info()
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# The SPAD map (RefGoodSpadMap) is read by
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# VL53L0X_get_info_from_device() in the API, but the same data seems to
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# be more easily readable from GLOBAL_CONFIG_SPAD_ENABLES_REF_0 through
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# _6, so read it from there.
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ref_spad_map = bytearray(7)
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self._i2c.readfrom_mem_into(self.address, _GLOBAL_CONFIG_SPAD_ENABLES_REF_0, ref_spad_map)
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for pair in (
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(0xFF, 0x01),
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(_DYNAMIC_SPAD_REF_EN_START_OFFSET, 0x00),
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(_DYNAMIC_SPAD_NUM_REQUESTED_REF_SPAD, 0x2C),
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(0xFF, 0x00),
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(_GLOBAL_CONFIG_REF_EN_START_SELECT, 0xB4),
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):
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self._write_u8(pair[0], pair[1])
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first_spad_to_enable = 12 if spad_is_aperture else 0
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spads_enabled = 0
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for i in range(48):
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if i < first_spad_to_enable or spads_enabled == spad_count:
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# This bit is lower than the first one that should be enabled,
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# or (reference_spad_count) bits have already been enabled, so
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# zero this bit.
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ref_spad_map[1 + (i // 8)] &= ~(1 << (i % 8))
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elif (ref_spad_map[1 + (i // 8)] >> (i % 8)) & 0x1 > 0:
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spads_enabled += 1
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self._i2c.writeto_mem(self.address, _GLOBAL_CONFIG_SPAD_ENABLES_REF_0, ref_spad_map)
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for pair in (
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(0xFF, 0x01),
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(0x00, 0x00),
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(0xFF, 0x00),
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(0x09, 0x00),
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(0x10, 0x00),
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(0x11, 0x00),
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(0x24, 0x01),
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(0x25, 0xFF),
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(0x75, 0x00),
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(0xFF, 0x01),
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(0x4E, 0x2C),
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(0x48, 0x00),
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(0x30, 0x20),
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(0xFF, 0x00),
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(0x30, 0x09),
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(0x54, 0x00),
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(0x31, 0x04),
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(0x32, 0x03),
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(0x40, 0x83),
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(0x46, 0x25),
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(0x60, 0x00),
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(0x27, 0x00),
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(0x50, 0x06),
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(0x51, 0x00),
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(0x52, 0x96),
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(0x56, 0x08),
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(0x57, 0x30),
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(0x61, 0x00),
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(0x62, 0x00),
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(0x64, 0x00),
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(0x65, 0x00),
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(0x66, 0xA0),
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(0xFF, 0x01),
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(0x22, 0x32),
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(0x47, 0x14),
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(0x49, 0xFF),
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(0x4A, 0x00),
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(0xFF, 0x00),
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(0x7A, 0x0A),
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(0x7B, 0x00),
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(0x78, 0x21),
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(0xFF, 0x01),
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(0x23, 0x34),
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(0x42, 0x00),
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(0x44, 0xFF),
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(0x45, 0x26),
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(0x46, 0x05),
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(0x40, 0x40),
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(0x0E, 0x06),
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(0x20, 0x1A),
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(0x43, 0x40),
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(0xFF, 0x00),
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(0x34, 0x03),
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(0x35, 0x44),
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(0xFF, 0x01),
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(0x31, 0x04),
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(0x4B, 0x09),
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(0x4C, 0x05),
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(0x4D, 0x04),
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(0xFF, 0x00),
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(0x44, 0x00),
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(0x45, 0x20),
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(0x47, 0x08),
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(0x48, 0x28),
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(0x67, 0x00),
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(0x70, 0x04),
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(0x71, 0x01),
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(0x72, 0xFE),
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(0x76, 0x00),
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(0x77, 0x00),
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(0xFF, 0x01),
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(0x0D, 0x01),
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(0xFF, 0x00),
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(0x80, 0x01),
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(0x01, 0xF8),
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(0xFF, 0x01),
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(0x8E, 0x01),
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(0x00, 0x01),
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(0xFF, 0x00),
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(0x80, 0x00),
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):
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self._write_u8(pair[0], pair[1])
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self._write_u8(_SYSTEM_INTERRUPT_CONFIG_GPIO, 0x04)
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gpio_hv_mux_active_high = self._read_u8(_GPIO_HV_MUX_ACTIVE_HIGH)
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self._write_u8(
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_GPIO_HV_MUX_ACTIVE_HIGH, gpio_hv_mux_active_high & ~0x10
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) # active low
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self._write_u8(_SYSTEM_INTERRUPT_CLEAR, 0x01)
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self._measurement_timing_budget_us = self.measurement_timing_budget
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self._write_u8(_SYSTEM_SEQUENCE_CONFIG, 0xE8)
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self.measurement_timing_budget = self._measurement_timing_budget_us
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self._write_u8(_SYSTEM_SEQUENCE_CONFIG, 0x01)
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self._perform_single_ref_calibration(0x40)
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self._write_u8(_SYSTEM_SEQUENCE_CONFIG, 0x02)
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self._perform_single_ref_calibration(0x00)
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# "restore the previous Sequence Config"
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self._write_u8(_SYSTEM_SEQUENCE_CONFIG, 0xE8)
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def _read_u8(self, register):
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# Read an 8-bit unsigned value from the specified 8-bit address.
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data = self._i2c.readfrom_mem(self.address, register, 1)
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return int.from_bytes(data, 'big')
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def _read_u16(self, register):
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# Read a 16-bit BE unsigned value from the specified 8-bit address.
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data = self._i2c.readfrom_mem(self.address, register, 2)
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return int.from_bytes(data, 'big')
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def _write_u8(self, register, val):
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# Write an 8-bit unsigned value to the specified 8-bit address.
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self._i2c.writeto_mem(self.address, register, val.to_bytes(1, 'big'))
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def _write_u16(self, register, val):
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# Write a 16-bit BE unsigned value to the specified 8-bit address.
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self._i2c.writeto_mem(self.address, register, val.to_bytes(2, 'big'))
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def _get_spad_info(self):
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# Get reference SPAD count and type, returned as a 2-tuple of
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# count and boolean is_aperture. Based on code from:
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# https://github.com/pololu/vl53l0x-arduino/blob/master/VL53L0X.cpp
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for pair in ((0x80, 0x01), (0xFF, 0x01), (0x00, 0x00), (0xFF, 0x06)):
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self._write_u8(pair[0], pair[1])
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self._write_u8(0x83, self._read_u8(0x83) | 0x04)
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for pair in (
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(0xFF, 0x07),
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(0x81, 0x01),
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(0x80, 0x01),
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(0x94, 0x6B),
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(0x83, 0x00),
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):
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self._write_u8(pair[0], pair[1])
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start = utime.ticks_ms() / 1000
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while self._read_u8(0x83) == 0x00:
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now = utime.ticks_ms() / 1000
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if now < start:
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start = utime.ticks_ms() / 1000
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if (
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self.io_timeout_s > 0
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and (now - start) >= self.io_timeout_s
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and now > start
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):
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raise RuntimeError("Timeout waiting for VL53L0X!")
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self._write_u8(0x83, 0x01)
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tmp = self._read_u8(0x92)
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count = tmp & 0x7F
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is_aperture = ((tmp >> 7) & 0x01) == 1
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for pair in ((0x81, 0x00), (0xFF, 0x06)):
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self._write_u8(pair[0], pair[1])
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self._write_u8(0x83, self._read_u8(0x83) & ~0x04)
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for pair in ((0xFF, 0x01), (0x00, 0x01), (0xFF, 0x00), (0x80, 0x00)):
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self._write_u8(pair[0], pair[1])
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return (count, is_aperture)
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def _perform_single_ref_calibration(self, vhv_init_byte):
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# based on VL53L0X_perform_single_ref_calibration() from ST API.
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self._write_u8(_SYSRANGE_START, 0x01 | vhv_init_byte & 0xFF)
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start = utime.ticks_ms() / 1000
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while (self._read_u8(_RESULT_INTERRUPT_STATUS) & 0x07) == 0:
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now = utime.ticks_ms() / 1000
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if now < start:
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now = utime.ticks_ms() / 1000
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if (
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self.io_timeout_s > 0
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and (now - start) >= self.io_timeout_s
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):
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raise RuntimeError("Timeout waiting for VL53L0X!")
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self._write_u8(_SYSTEM_INTERRUPT_CLEAR, 0x01)
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self._write_u8(_SYSRANGE_START, 0x00)
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def _get_vcsel_pulse_period(self, vcsel_period_type):
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# pylint: disable=no-else-return
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# Disable should be removed when refactor can be tested
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if vcsel_period_type == _VCSEL_PERIOD_PRE_RANGE:
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val = self._read_u8(_PRE_RANGE_CONFIG_VCSEL_PERIOD)
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return (((val) + 1) & 0xFF) << 1
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elif vcsel_period_type == _VCSEL_PERIOD_FINAL_RANGE:
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val = self._read_u8(_FINAL_RANGE_CONFIG_VCSEL_PERIOD)
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return (((val) + 1) & 0xFF) << 1
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return 255
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def _get_sequence_step_enables(self):
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# based on VL53L0X_GetSequenceStepEnables() from ST API
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sequence_config = self._read_u8(_SYSTEM_SEQUENCE_CONFIG)
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tcc = (sequence_config >> 4) & 0x1 > 0
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dss = (sequence_config >> 3) & 0x1 > 0
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msrc = (sequence_config >> 2) & 0x1 > 0
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pre_range = (sequence_config >> 6) & 0x1 > 0
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final_range = (sequence_config >> 7) & 0x1 > 0
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return (tcc, dss, msrc, pre_range, final_range)
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def _get_sequence_step_timeouts(self, pre_range):
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# based on get_sequence_step_timeout() from ST API but modified by
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# pololu here:
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# https://github.com/pololu/vl53l0x-arduino/blob/master/VL53L0X.cpp
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pre_range_vcsel_period_pclks = self._get_vcsel_pulse_period(
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_VCSEL_PERIOD_PRE_RANGE
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)
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msrc_dss_tcc_mclks = (self._read_u8(_MSRC_CONFIG_TIMEOUT_MACROP) + 1) & 0xFF
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msrc_dss_tcc_us = _timeout_mclks_to_microseconds(
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msrc_dss_tcc_mclks, pre_range_vcsel_period_pclks
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)
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pre_range_mclks = _decode_timeout(
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self._read_u16(_PRE_RANGE_CONFIG_TIMEOUT_MACROP_HI)
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)
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pre_range_us = _timeout_mclks_to_microseconds(
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pre_range_mclks, pre_range_vcsel_period_pclks
|
|
)
|
|
final_range_vcsel_period_pclks = self._get_vcsel_pulse_period(
|
|
_VCSEL_PERIOD_FINAL_RANGE
|
|
)
|
|
final_range_mclks = _decode_timeout(
|
|
self._read_u16(_FINAL_RANGE_CONFIG_TIMEOUT_MACROP_HI)
|
|
)
|
|
if pre_range:
|
|
final_range_mclks -= pre_range_mclks
|
|
final_range_us = _timeout_mclks_to_microseconds(
|
|
final_range_mclks, final_range_vcsel_period_pclks
|
|
)
|
|
return (
|
|
msrc_dss_tcc_us,
|
|
pre_range_us,
|
|
final_range_us,
|
|
final_range_vcsel_period_pclks,
|
|
pre_range_mclks,
|
|
)
|
|
|
|
@property
|
|
def signal_rate_limit(self):
|
|
"""The signal rate limit in mega counts per second."""
|
|
val = self._read_u16(_FINAL_RANGE_CONFIG_MIN_COUNT_RATE_RTN_LIMIT)
|
|
# Return value converted from 16-bit 9.7 fixed point to float.
|
|
return val / (1 << 7)
|
|
|
|
@signal_rate_limit.setter
|
|
def signal_rate_limit(self, val):
|
|
assert 0.0 <= val <= 511.99
|
|
# Convert to 16-bit 9.7 fixed point value from a float.
|
|
val = int(val * (1 << 7))
|
|
self._write_u16(_FINAL_RANGE_CONFIG_MIN_COUNT_RATE_RTN_LIMIT, val)
|
|
|
|
@property
|
|
def measurement_timing_budget(self):
|
|
"""The measurement timing budget in microseconds."""
|
|
budget_us = 1910 + 960 # Start overhead + end overhead.
|
|
tcc, dss, msrc, pre_range, final_range = self._get_sequence_step_enables()
|
|
step_timeouts = self._get_sequence_step_timeouts(pre_range)
|
|
msrc_dss_tcc_us, pre_range_us, final_range_us, _, _ = step_timeouts
|
|
if tcc:
|
|
budget_us += msrc_dss_tcc_us + 590
|
|
if dss:
|
|
budget_us += 2 * (msrc_dss_tcc_us + 690)
|
|
elif msrc:
|
|
budget_us += msrc_dss_tcc_us + 660
|
|
if pre_range:
|
|
budget_us += pre_range_us + 660
|
|
if final_range:
|
|
budget_us += final_range_us + 550
|
|
self._measurement_timing_budget_us = budget_us
|
|
return budget_us
|
|
|
|
@measurement_timing_budget.setter
|
|
def measurement_timing_budget(self, budget_us):
|
|
# pylint: disable=too-many-locals
|
|
assert budget_us >= 20000
|
|
used_budget_us = 1320 + 960 # Start (diff from get) + end overhead
|
|
tcc, dss, msrc, pre_range, final_range = self._get_sequence_step_enables()
|
|
step_timeouts = self._get_sequence_step_timeouts(pre_range)
|
|
msrc_dss_tcc_us, pre_range_us, _ = step_timeouts[:3]
|
|
final_range_vcsel_period_pclks, pre_range_mclks = step_timeouts[3:]
|
|
if tcc:
|
|
used_budget_us += msrc_dss_tcc_us + 590
|
|
if dss:
|
|
used_budget_us += 2 * (msrc_dss_tcc_us + 690)
|
|
elif msrc:
|
|
used_budget_us += msrc_dss_tcc_us + 660
|
|
if pre_range:
|
|
used_budget_us += pre_range_us + 660
|
|
if final_range:
|
|
used_budget_us += 550
|
|
# "Note that the final range timeout is determined by the timing
|
|
# budget and the sum of all other timeouts within the sequence.
|
|
# If there is no room for the final range timeout, then an error
|
|
# will be set. Otherwise the remaining time will be applied to
|
|
# the final range."
|
|
if used_budget_us > budget_us:
|
|
raise ValueError("Requested timeout too big.")
|
|
final_range_timeout_us = budget_us - used_budget_us
|
|
final_range_timeout_mclks = _timeout_microseconds_to_mclks(
|
|
final_range_timeout_us, final_range_vcsel_period_pclks
|
|
)
|
|
if pre_range:
|
|
final_range_timeout_mclks += pre_range_mclks
|
|
self._write_u16(
|
|
_FINAL_RANGE_CONFIG_TIMEOUT_MACROP_HI,
|
|
_encode_timeout(final_range_timeout_mclks),
|
|
)
|
|
self._measurement_timing_budget_us = budget_us
|
|
|
|
def start_range_request(self):
|
|
if self.range_started == True: return # Already started
|
|
"""Start a single reading of the range for an object in front of
|
|
the sensor. This is used both for blocking range requests (called
|
|
by the .range property), and non-blocking range requests in the form:
|
|
sensor.start_range_request()
|
|
...
|
|
if sensor.reading_available():
|
|
print(sensor.get_range_value())
|
|
"""
|
|
# Adapted from readRangeSingleMillimeters &
|
|
# readRangeContinuousMillimeters in pololu code at:
|
|
# https://github.com/pololu/vl53l0x-arduino/blob/master/VL53L0X.cpp
|
|
for pair in (
|
|
(0x80, 0x01),
|
|
(0xFF, 0x01),
|
|
(0x00, 0x00),
|
|
(0x91, self._stop_variable),
|
|
(0x00, 0x01),
|
|
(0xFF, 0x00),
|
|
(0x80, 0x00),
|
|
(_SYSRANGE_START, 0x01),
|
|
):
|
|
self._write_u8(pair[0], pair[1])
|
|
self.range_started = True
|
|
|
|
# Return true if a range request initiated by start_range_request
|
|
# is available to be read via self.get_range_value().
|
|
def reading_available(self):
|
|
if self.range_started == False: return False
|
|
if (self._read_u8(_RESULT_INTERRUPT_STATUS) & 0x07) == 0: return False
|
|
return True
|
|
|
|
# After start_range_request(), once the sensor completed a reading
|
|
# this function will return the final range value in millimeters.
|
|
# As a side effect this function will also clear the interrupt status
|
|
# flag.
|
|
def get_range_value(self):
|
|
if self.range_started == False: return None
|
|
|
|
# assumptions: Linearity Corrective Gain is 1000 (default)
|
|
# fractional ranging is not enabled
|
|
range_mm = self._read_u16(_RESULT_RANGE_STATUS + 10)
|
|
self._write_u8(_SYSTEM_INTERRUPT_CLEAR, 0x01)
|
|
self.range_started = False # Don't return the same data again.
|
|
return range_mm
|
|
|
|
@property
|
|
def range(self):
|
|
# If there is a non-blocking measure ongoing, don't initiate
|
|
# a blocking one.
|
|
if self.range_started: return None
|
|
|
|
self.start_range_request()
|
|
|
|
start = utime.ticks_ms()
|
|
while self.reading_available() == False:
|
|
if (utime.ticks_diff(utime.ticks_ms(),start) > 1000):
|
|
raise RuntimeError("Timeout waiting for VL53L0X!")
|
|
utime.sleep_ms(5)
|
|
|
|
return self.get_range_value()
|
|
|
|
def set_address(self, new_address):
|
|
self._write_u8(_I2C_SLAVE_DEVICE_ADDRESS, new_address & 0x7F)
|
|
# self._device = i2c_device.I2CDevice(self._i2c, new_address)
|
|
print("new address is ")
|
|
return new_address
|
|
|