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Diffstat (limited to 'klippy/extras/sht3x.py')
| -rw-r--r-- | klippy/extras/sht3x.py | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/klippy/extras/sht3x.py b/klippy/extras/sht3x.py new file mode 100644 index 00000000..699d3f20 --- /dev/null +++ b/klippy/extras/sht3x.py @@ -0,0 +1,165 @@ +# SHT3X i2c based temperature sensors support +# +# Copyright (C) 2024 Timofey Titovets <nefelim4ag@gmail.com> +# Based on htu21d.py code +# +# This file may be distributed under the terms of the GNU GPLv3 license. +import logging +from . import bus + +###################################################################### +# Compatible Sensors: +# SHT31 - Tested on octopus pro and Linux MCU +# +###################################################################### +SHT3X_I2C_ADDR = 0x44 + +SHT3X_CMD = { + 'MEASURE': { + 'STRETCH_ENABLED': { + 'HIGH_REP': [0x2c, 0x06], # High (15ms) repeatability measurement + 'MED_REP': [0x2c, 0x0D], # Medium (6ms) repeatability measurement + 'LOW_REP': [0x2c, 0x10], # Low (4ms) repeatability measurement + }, + 'STRETCH_DISABLED' : { + 'HIGH_REP': [0x24, 0x00], + 'MED_REP': [0x24, 0x0B], + 'LOW_REP': [0x24, 0x16], + }, + }, + 'OTHER': { + 'STATUS': { + 'READ': [0xF3, 0x2D], + 'CLEAN': [0x30, 0x41], + }, + 'SOFTRESET': [0x30, 0xA2], # Soft reset + 'HEATER': { + "ENABLE": [0x30, 0x6D], + "DISABLE": [0x30, 0x66], + }, + 'FETCH': [0xE0, 0x00], + 'BREAK': [0x30, 0x93], + } +} + +class SHT3X: + def __init__(self, config): + self.printer = config.get_printer() + self.name = config.get_name().split()[-1] + self.reactor = self.printer.get_reactor() + self.i2c = bus.MCU_I2C_from_config( + config, default_addr=SHT3X_I2C_ADDR, default_speed=100000) + self.report_time = config.getint('sht3x_report_time', 1, minval=1) + self.deviceId = config.get('sensor_type') + self.temp = self.min_temp = self.max_temp = self.humidity = 0. + self.sample_timer = self.reactor.register_timer(self._sample_sht3x) + self.printer.add_object("sht3x " + self.name, self) + self.printer.register_event_handler("klippy:connect", + self.handle_connect) + def handle_connect(self): + self._init_sht3x() + self.reactor.update_timer(self.sample_timer, self.reactor.NOW) + + def setup_minmax(self, min_temp, max_temp): + self.min_temp = min_temp + self.max_temp = max_temp + + def setup_callback(self, cb): + self._callback = cb + + def get_report_time_delta(self): + return self.report_time + + def _init_sht3x(self): + # Device Soft Reset + self.i2c.i2c_write(SHT3X_CMD['OTHER']['SOFTRESET']) + + # Wait 2ms after reset + self.reactor.pause(self.reactor.monotonic() + .02) + + status = self.i2c.i2c_read(SHT3X_CMD['OTHER']['STATUS']['READ'], 3) + response = bytearray(status['response']) + status = response[0] << 8 + status |= response[1] + checksum = response[2] + + if self._crc8(status) != checksum: + logging.warning("sht3x: Reading status - checksum error!") + + def _sample_sht3x(self, eventtime): + try: + # Read Temeprature + params = self.i2c.i2c_write( + SHT3X_CMD['MEASURE']['STRETCH_ENABLED']['HIGH_REP'] + ) + # Wait + self.reactor.pause(self.reactor.monotonic() + + .20) + + params = self.i2c.i2c_read([], 6) + + response = bytearray(params['response']) + rtemp = response[0] << 8 + rtemp |= response[1] + if self._crc8(rtemp) != response[2]: + logging.warning( + "sht3x: Checksum error on Temperature reading!" + ) + else: + self.temp = -45 + (175 * rtemp / 65535) + logging.debug("sht3x: Temperature %.2f " % self.temp) + + rhumid = response[3] << 8 + rhumid |= response[4] + if self._crc8(rhumid) != response[5]: + logging.warning("sht3x: Checksum error on Humidity reading!") + else: + self.humidity = 100 * rhumid / 65535 + logging.debug("sht3x: Humidity %.2f " % self.humidity) + + except Exception: + logging.exception("sht3x: Error reading data") + self.temp = self.humidity = .0 + return self.reactor.NEVER + + if self.temp < self.min_temp or self.temp > self.max_temp: + self.printer.invoke_shutdown( + "sht3x: temperature %0.1f outside range of %0.1f:%.01f" + % (self.temp, self.min_temp, self.max_temp)) + + measured_time = self.reactor.monotonic() + print_time = self.i2c.get_mcu().estimated_print_time(measured_time) + self._callback(print_time, self.temp) + return measured_time + self.report_time + + def _split_bytes(self, data): + bytes = [] + for i in range((data.bit_length() + 7) // 8): + bytes.append((data >> i*8) & 0xFF) + bytes.reverse() + return bytes + + def _crc8(self, data): + #crc8 polynomial for 16bit value, CRC8 -> x^8 + x^5 + x^4 + 1 + SHT3X_CRC8_POLYNOMINAL= 0x31 + crc = 0xFF + data_bytes = self._split_bytes(data) + for byte in data_bytes: + crc ^= byte + for _ in range(8): + if crc & 0x80: + crc = (crc << 1) ^ SHT3X_CRC8_POLYNOMINAL + else: + crc <<= 1 + return crc & 0xFF + + def get_status(self, eventtime): + return { + 'temperature': round(self.temp, 2), + 'humidity': round(self.humidity, 1), + } + +def load_config(config): + # Register sensor + pheater = config.get_printer().lookup_object("heaters") + pheater.add_sensor_factory("SHT3X", SHT3X) |