From 713b50969848910d52c7d91dce695140bb59df9d Mon Sep 17 00:00:00 2001
From: Timofey Titovets <nefelim4ag@gmail.com>
Date: Sun, 21 Apr 2024 00:42:31 +0200
Subject: [PATCH] sht3x: Add sht31 support (#6560)
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
---
docs/Config_Reference.md | 19 +++
docs/Status_Reference.md | 3 +-
klippy/extras/sht3x.py | 165 ++++++++++++++++++++++++++
klippy/extras/temperature_sensors.cfg | 2 +
4 files changed, 188 insertions(+), 1 deletion(-)
create mode 100644 klippy/extras/sht3x.py
diff --git a/docs/Config_Reference.md b/docs/Config_Reference.md
index 403dfdfc4..71cdfed87 100644
--- a/docs/Config_Reference.md
+++ b/docs/Config_Reference.md
@@ -2575,6 +2575,25 @@ sensor_type:
# Interval in seconds between readings. Default is 30
```
+### SHT3X sensor
+
+SHT3X family two wire interface (I2C) environmental sensor. These sensors
+have a range of -55~125 C, so are usable for e.g. chamber temperature
+monitoring. They can also function as simple fan/heater controllers.
+
+```
+sensor_type: SHT3X
+#i2c_address:
+# Default is 68 (0x44).
+#i2c_mcu:
+#i2c_bus:
+#i2c_software_scl_pin:
+#i2c_software_sda_pin:
+#i2c_speed:
+# See the "common I2C settings" section for a description of the
+# above parameters.
+```
+
### LM75 temperature sensor
LM75/LM75A two wire (I2C) connected temperature sensors. These sensors
diff --git a/docs/Status_Reference.md b/docs/Status_Reference.md
index 0e72a12b1..66d840d16 100644
--- a/docs/Status_Reference.md
+++ b/docs/Status_Reference.md
@@ -445,6 +445,7 @@ The following information is available in
[bme280 config_section_name](Config_Reference.md#bmp280bme280bme680-temperature-sensor),
[htu21d config_section_name](Config_Reference.md#htu21d-sensor),
+[sht3x config_section_name](Config_Reference.md#sht31-sensor),
[lm75 config_section_name](Config_Reference.md#lm75-temperature-sensor),
[temperature_host config_section_name](Config_Reference.md#host-temperature-sensor)
and
@@ -452,7 +453,7 @@ and
objects:
- `temperature`: The last read temperature from the sensor.
- `humidity`, `pressure`, `gas`: The last read values from the sensor
- (only on bme280, htu21d, and lm75 sensors).
+ (only on bme280, htu21d, sht3x and lm75 sensors).
## temperature_fan
diff --git a/klippy/extras/sht3x.py b/klippy/extras/sht3x.py
new file mode 100644
index 000000000..699d3f209
--- /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)
diff --git a/klippy/extras/temperature_sensors.cfg b/klippy/extras/temperature_sensors.cfg
index 107fcd24b..4fbe5492c 100644
--- a/klippy/extras/temperature_sensors.cfg
+++ b/klippy/extras/temperature_sensors.cfg
@@ -18,6 +18,8 @@
# Load "SI7013", "SI7020", "SI7021", "SHT21", and "HTU21D" sensors
[htu21d]
+[sht3x]
+
# Load "AHT10"
[aht10]