Version bump to v0.2.0

.gitignore

@@ -18,7 +18,6 @@ dist/
 downloads/
 eggs/
 .eggs/
-lib/
 lib64/
 parts/
 sdist/

README.md

@@ -1,20 +1,61 @@
 # pico-thermo
 
 ![Woodpecker CI badge](https://builds.metaunix.net/api/badges/90/status.svg)
+![shields.io version badge](https://img.shields.io/gitea/v/release/BitGoblin/pico-thermo?gitea_url=https://git.metaunix.net)
 
-MicroPython app to read data from BME280 sensor and send it to Home Assistant
+A [MicroPython](https://micropython.org/) app to read data from BME280 sensor and send it to Home Assistant.
 
-## Running
+## Hardware
 
-Flash your Raspberry Pi Pico with MicroPython.
+The following hardware is what I used for a deployment:
 
-Copy `config.example.py` to `config.py` and edit the settings to match your environment.
+* Raspberry Pi Pico 2 W: https://www.amazon.com/dp/B0DRJXPPWL
+  * The **W** is VERY important, as without networking it can't reach Home Assistant!
+  * Also a Raspberry Pi Pico W *should* work too, but I haven't tested it yet
+* Waveshare Bosch BME280 sensor: https://www.amazon.com/dp/B07Q47DFXS
+* Elegoo SSD1306 LCD: https://www.amazon.com/dp/B0FSRQG23K
 
-Copy `main.py` and `config.py` to the root of the filesystem on the Pico.
+Most (or all?) of these components can be swapped for equivalent components. You just need to make sure the code is compatible with whatever board you choose (not likely), is a genuine BME280 sensor, and an SSD1306 display.
 
-Connect the BME280 sensor to your Pico and power on.
+Support for other hardware types may come in the future, but if there's a specific sensor or board you're interested in, please submit an issue or pull request!
 
-Head on to your Home Assistant instance and enjoy!
+### Prototyping
+
+To help with debugging/testing deployments, I also used these components:
+
+* Elegoo 400-pin Breadboard: https://www.amazon.com/dp/B01EV640I6
+* Freenove Raspberry Pi Pico Breakout Board: https://www.amazon.com/dp/B0BFB53Y2N
+* Elegoo 20cm Jumper Cables 120 count: https://www.amazon.com/dp/B01EV70C78
+
+These are not necessary to run the app, but can be useful for testing and/or flashing several nodes.
+
+## Software Deployment
+
+### Requirements
+
+* [MicroPython](https://micropython.org/download/) - MicroPython downloads
+* [mpremote](https://docs.micropython.org/en/latest/reference/mpremote.html) - MicroPython remote serial tool
+* (Linux users) Your user should be a part of the `dialout` group
+
+### Steps
+
+1. Connect your BME280 sensor and SSD1306 display to your Pico.
+    1. You *may* need a breadboard for this, else you can use splitters.
+2. Connect your Pico to your PC via a micro-USB to USB type-A cable.
+3. [Flash your Raspberry Pi Pico with MicroPython](https://docs.micropython.org/en/latest/rp2/tutorial/reset.html).
+    1. This has been tested with MicroPython 1.29, but other versions should work.
+4. Clone this git repository: `git clone https://git.metaunix.net/BitGoblin/pico-time`.
+5. `cd` into the repo: `cd pico-time`.
+6. Install Python dependencies via mpremote: `mpremote mip install ./package.json`.
+7. Copy `config.example.py` to `config.py` and edit the settings to match your environment.
+8. Copy the Python code over to the Pico:
+    1. `mpremote cp main.py :main.py`
+    2. `mpremote cp config.py :config.py`
+9. Reset the Pico: `mpremote reset`
+
+There's also `./install.sh` if you'd like to run steps 6-9 more quickly.
+
+If it worked you should see the display show a message about connecting to WiFi, then eventually a readout of the current temperature to the SSD1306 display. If it failed, you can monitor the app via `mpremote repl` or using an IDE like [Thonny](https://thonny.org/).
 
 ## License
 

config.example.py

@@ -12,3 +12,6 @@ MQTT_PASS = "mqtt_password"  # MQTT password (leave blank for no login)
 NODE_NAME = "Room Weather"  # Name that's displayed on HA Device Card
 NODE_ID = "room_env"  # Unique slug for entity_id and MQTT topic path
 CLIENT_ID = f"pico2w_{NODE_ID}"  # Unique client ID used by the MQTT broker
+
+# Sensor selection: "bme280" or "sht41"
+SENSOR_TYPE = "bme280"

install.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+APP_FILES=('main.py' 'config.py' 'lib/')
+APP_PACKAGES='./package.json'
+
+# Copy required files
+mpremote cp -r "${APP_FILES[@]}" :
+
+# Install dependencies
+mpremote mip install ./package.json
+
+# Reset the pico
+mpremote reset

lib/bme280.py

@@ -0,0 +1,101 @@
+import struct
+import time
+
+
+class BME280:
+    DEFAULT_ADDR = 0x77
+
+    def __init__(self, i2c, addr=DEFAULT_ADDR):
+        self.i2c = i2c
+        self.addr = addr
+
+        # Reset sensor
+        self.i2c.writeto_mem(self.addr, 0xE0, b"\xb6")
+        time.sleep(0.1)
+
+        self._read_calibration_data()
+
+        # Humidity oversampling x1
+        self.i2c.writeto_mem(self.addr, 0xF2, b"\x01")
+        # Pressure oversampling x1, Temp oversampling x1, Normal mode
+        self.i2c.writeto_mem(self.addr, 0xF4, b"\x27")
+        # Standby 1000ms, filter off
+        self.i2c.writeto_mem(self.addr, 0xF5, b"\xa0")
+
+    def _read_calibration_data(self):
+        calib = self.i2c.readfrom_mem(self.addr, 0x88, 24)
+        c = struct.unpack("<HhhHhhhhhhhh", calib)
+        self.dig_t1, self.dig_t2, self.dig_t3 = c[0], c[1], c[2]
+        self.dig_p1, self.dig_p2, self.dig_p3 = c[3], c[4], c[5]
+        self.dig_p4, self.dig_p5, self.dig_p6 = c[6], c[7], c[8]
+        self.dig_p7, self.dig_p8, self.dig_p9 = c[9], c[10], c[11]
+
+        self.dig_h1 = self.i2c.readfrom_mem(self.addr, 0xA1, 1)[0]
+        h = struct.unpack("<hB", self.i2c.readfrom_mem(self.addr, 0xE1, 3)[:3])
+        self.dig_h2, self.dig_h3 = h[0], h[1]
+
+        e4 = self.i2c.readfrom_mem(self.addr, 0xE4, 2)
+        self.dig_h4 = (e4[0] << 4) | (e4[1] & 0x0F)
+
+        e5_e6 = self.i2c.readfrom_mem(self.addr, 0xE5, 2)
+        self.dig_h5 = (e5_e6[0] >> 4) | (e5_e6[1] << 4)
+
+        self.dig_h6 = struct.unpack("<b", self.i2c.readfrom_mem(self.addr, 0xE7, 1))[0]
+
+    def read_values(self):
+        raw = self.i2c.readfrom_mem(self.addr, 0xF7, 8)
+        raw_p = ((raw[0] << 16) | (raw[1] << 8) | raw[2]) >> 4
+        raw_t = ((raw[3] << 16) | (raw[4] << 8) | raw[5]) >> 4
+        raw_h = (raw[6] << 8) | raw[7]
+
+        # Temperature calculation (Celsius)
+        var1 = (((raw_t >> 3) - (self.dig_t1 << 1)) * self.dig_t2) >> 11
+        var2 = (
+            (((raw_t >> 4) - self.dig_t1) * ((raw_t >> 4) - self.dig_t1)) >> 12
+        ) * self.dig_t3 >> 14
+        t_fine = var1 + var2
+        temp = ((t_fine * 5 + 128) >> 8) / 100.0
+
+        # Pressure calculation (hPa)
+        p_var1 = t_fine - 128000
+        p_var2 = (
+            p_var1 * p_var1 * self.dig_p6 + ((p_var1 * self.dig_p5) << 17) + (self.dig_p4 << 35)
+        )
+        p_var1 = ((p_var1 * p_var1 * self.dig_p3) >> 8) + ((p_var1 * self.dig_p2) << 12)
+        p_var1 = (((1 << 47) + p_var1) * self.dig_p1) >> 33
+
+        if p_var1 == 0:
+            pressure = 0.0
+        else:
+            p = 1048576 - raw_p
+            p = (((p << 31) - p_var2) * 3125) // p_var1
+            p_var1 = (self.dig_p9 * (p >> 13) * (p >> 13)) >> 25
+            p_var2 = (self.dig_p8 * p) >> 19
+            p = ((p + p_var1 + p_var2) >> 8) + (self.dig_p7 << 4)
+            pressure = (p / 256.0) / 100.0
+
+        # Humidity calculation (%)
+        h_var = t_fine - 76800
+        h_var = ((((raw_h << 14) - (self.dig_h4 << 20) - (self.dig_h5 * h_var)) + 16384) >> 15) * (
+            (
+                (
+                    (
+                        (((h_var * self.dig_h6) >> 10) * (((h_var * self.dig_h3) >> 11) + 32768))
+                        >> 10
+                    )
+                    + 2097152
+                )
+                * self.dig_h2
+                + 8192
+            )
+            >> 14
+        )
+        h_var = h_var - (((((h_var >> 15) * (h_var >> 15)) >> 7) * self.dig_h1) >> 4)
+        h_var = max(0, min(h_var, 419430400))
+        humidity = (h_var >> 12) / 1024.0
+
+        return {
+            "temperature": round(temp, 2),
+            "pressure": round(pressure, 2),
+            "humidity": round(humidity, 2),
+        }

lib/sht41.py

@@ -0,0 +1,36 @@
+import time
+
+
+class SHT41:
+    DEFAULT_ADDR = 0x44
+    CMD_MEASURE_HIGH_PRECISION = 0xFD
+
+    def __init__(self, i2c, addr=DEFAULT_ADDR):
+        self.i2c = i2c
+        self.addr = addr
+        # Soft reset
+        self.i2c.writeto(self.addr, b"\x94")
+        time.sleep(0.01)
+
+    def read_values(self):
+        # Trigger high precision measurement
+        self.i2c.writeto(self.addr, bytes([self.CMD_MEASURE_HIGH_PRECISION]))
+        # Conversion takes up to 8.2ms
+        time.sleep(0.01)
+
+        # 6 bytes: [Temp_MSB, Temp_LSB, CRC, Hum_MSB, Hum_LSB, CRC]
+        data = self.i2c.readfrom(self.addr, 6)
+
+        raw_t = (data[0] << 8) | data[1]
+        raw_h = (data[3] << 8) | data[4]
+
+        # Sensirion SHT4x conversion equations
+        temp = -45.0 + 175.0 * (raw_t / 65535.0)
+        hum = -6.0 + 125.0 * (raw_h / 65535.0)
+        hum = max(0.0, min(hum, 100.0))
+
+        return {
+            "temperature": round(temp, 2),
+            "humidity": round(hum, 2),
+            "pressure": None,
+        }

lib/simple_mqtt.py

@@ -0,0 +1,78 @@
+import socket
+import struct
+
+
+class SimpleMQTT:
+    def __init__(self, host, port=1883):
+        self.host = host
+        self.port = port
+        self.sock = None
+
+    def connect(self, client_id, username=None, password=None):
+        addr_info = socket.getaddrinfo(self.host, self.port)
+        addr = addr_info[0][-1]
+        self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.sock.connect(addr)
+
+        # Flags: Clean session (bit 1) + optional credentials
+        flags = 0x02
+        if username:
+            flags |= 0x80
+        if password:
+            flags |= 0x40
+
+        # Variable header: Protocol Name (MQTT) + Level (4) + Flags + KeepAlive (60s)
+        var_header = bytearray(
+            [0x00, 0x04, ord("M"), ord("Q"), ord("T"), ord("T"), 0x04, flags, 0x00, 0x3C]
+        )
+
+        payload = bytearray()
+        payload.extend(self._encode_str(client_id))
+        if username:
+            payload.extend(self._encode_str(username))
+        if password:
+            payload.extend(self._encode_str(password))
+
+        body = var_header + payload
+        packet = bytearray([0x10]) + self._encode_len(len(body)) + body
+        self.sock.write(packet)
+
+        # Read CONNACK (4 bytes: 0x20, 0x02, ack_flags, return_code)
+        resp = self.sock.read(4)
+        if not resp or resp[0] != 0x20 or resp[3] != 0x00:
+            code = resp[3] if resp and len(resp) >= 4 else "nil"
+            raise RuntimeError(f"MQTT connection failed: code {code}")
+
+    def publish(self, topic, payload, retain=False):
+        cmd = 0x30 | (0x01 if retain else 0x00)
+        if isinstance(payload, str):
+            payload = payload.encode("utf-8")
+        body = self._encode_str(topic) + payload
+        packet = bytearray([cmd]) + self._encode_len(len(body)) + body
+        self.sock.write(packet)
+
+    def disconnect(self):
+        try:
+            if self.sock:
+                self.sock.write(bytearray([0xE0, 0x00]))
+                self.sock.close()
+        except Exception:
+            pass
+        finally:
+            self.sock = None
+
+    def _encode_str(self, s):
+        raw = s.encode("utf-8")
+        return struct.pack("!H", len(raw)) + raw
+
+    def _encode_len(self, length):
+        encoded = bytearray()
+        while True:
+            digit = length % 128
+            length //= 128
+            if length > 0:
+                digit |= 0x80
+            encoded.append(digit)
+            if length == 0:
+                break
+        return encoded

main.py

@@ -1,8 +1,8 @@
-import socket
-import struct
 import time
 from machine import Pin, SoftI2C
+import json
 import network
+from simple_mqtt import SimpleMQTT
 
 # -------------------------------------------------------------
 # Configuration Loader
@@ -15,206 +15,29 @@ except ImportError:
     while True:
         time.sleep(2)
 
-# Default NODE_NAME to NODE_ID if not explicitly provided in config.py
 NODE_NAME = getattr(Config, "NODE_NAME", Config.NODE_ID)
+SENSOR_TYPE = getattr(Config, "SENSOR_TYPE", "bme280").lower()
 STATE_TOPIC = f"homeassistant/sensor/{Config.NODE_ID}/state"
 
-
-# -------------------------------------------------------------
-# Minimal MQTT 3.1.1 Client
-# -------------------------------------------------------------
-class SimpleMQTT:
-    def __init__(self, host, port=1883):
-        self.host = host
-        self.port = port
-        self.sock = None
-
-    def connect(self, client_id, username=None, password=None):
-        addr_info = socket.getaddrinfo(self.host, self.port)
-        addr = addr_info[0][-1]
-        self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-        self.sock.connect(addr)
-
-        # Flags: Clean session (bit 1) + optional credentials
-        flags = 0x02
-        if username:
-            flags |= 0x80
-        if password:
-            flags |= 0x40
-
-        # Variable header: Protocol Name (MQTT) + Level (4) + Flags + KeepAlive (60s)
-        var_header = bytearray(
-            [0x00, 0x04, ord("M"), ord("Q"), ord("T"), ord("T"), 0x04, flags, 0x00, 0x3C]
-        )
-
-        # Payload
-        payload = bytearray()
-        payload.extend(self._encode_str(client_id))
-        if username:
-            payload.extend(self._encode_str(username))
-        if password:
-            payload.extend(self._encode_str(password))
-
-        body = var_header + payload
-        packet = bytearray([0x10]) + self._encode_len(len(body)) + body
-        self.sock.write(packet)
-
-        # Read CONNACK (4 bytes: 0x20, 0x02, ack_flags, return_code)
-        resp = self.sock.read(4)
-        if not resp or resp[0] != 0x20 or resp[3] != 0x00:
-            code = resp[3] if resp and len(resp) >= 4 else "nil"
-            raise RuntimeError(f"MQTT connection failed: code {code}")
-
-    def publish(self, topic, payload, retain=False):
-        cmd = 0x30 | (0x01 if retain else 0x00)
-        if isinstance(payload, str):
-            payload = payload.encode("utf-8")
-        body = self._encode_str(topic) + payload
-        packet = bytearray([cmd]) + self._encode_len(len(body)) + body
-        self.sock.write(packet)
-
-    def disconnect(self):
-        try:
-            if self.sock:
-                self.sock.write(bytearray([0xE0, 0x00]))
-                self.sock.close()
-        except Exception:
-            pass
-        finally:
-            self.sock = None
-
-    def _encode_str(self, s):
-        raw = s.encode("utf-8")
-        return struct.pack("!H", len(raw)) + raw
-
-    def _encode_len(self, length):
-        encoded = bytearray()
-        while True:
-            digit = length % 128
-            length //= 128
-            if length > 0:
-                digit |= 0x80
-            encoded.append(digit)
-            if length == 0:
-                break
-        return encoded
-
-
-# -------------------------------------------------------------
-# BME280 Driver (I2C)
-# -------------------------------------------------------------
-class BME280:
-    DEFAULT_ADDR = 0x77
-
-    def __init__(self, i2c, addr=DEFAULT_ADDR):
-        self.i2c = i2c
-        self.addr = addr
-
-        # Reset sensor
-        self.i2c.writeto_mem(self.addr, 0xE0, b"\xb6")
-        time.sleep(0.1)
-
-        self._read_calibration_data()
-
-        # Humidity oversampling x1
-        self.i2c.writeto_mem(self.addr, 0xF2, b"\x01")
-        # Pressure oversampling x1, Temp oversampling x1, Normal mode
-        self.i2c.writeto_mem(self.addr, 0xF4, b"\x27")
-        # Standby 1000ms, filter off
-        self.i2c.writeto_mem(self.addr, 0xF5, b"\xa0")
-
-    def _read_calibration_data(self):
-        calib = self.i2c.readfrom_mem(self.addr, 0x88, 24)
-        c = struct.unpack("<HhhHhhhhhhhh", calib)
-        self.dig_t1, self.dig_t2, self.dig_t3 = c[0], c[1], c[2]
-        self.dig_p1, self.dig_p2, self.dig_p3 = c[3], c[4], c[5]
-        self.dig_p4, self.dig_p5, self.dig_p6 = c[6], c[7], c[8]
-        self.dig_p7, self.dig_p8, self.dig_p9 = c[9], c[10], c[11]
-
-        self.dig_h1 = self.i2c.readfrom_mem(self.addr, 0xA1, 1)[0]
-        h = struct.unpack("<hB", self.i2c.readfrom_mem(self.addr, 0xE1, 3)[:3])
-        self.dig_h2, self.dig_h3 = h[0], h[1]
-
-        e4 = self.i2c.readfrom_mem(self.addr, 0xE4, 2)
-        self.dig_h4 = (e4[0] << 4) | (e4[1] & 0x0F)
-
-        e5_e6 = self.i2c.readfrom_mem(self.addr, 0xE5, 2)
-        self.dig_h5 = (e5_e6[0] >> 4) | (e5_e6[1] << 4)
-
-        self.dig_h6 = struct.unpack("<b", self.i2c.readfrom_mem(self.addr, 0xE7, 1))[0]
-
-    def read_values(self):
-        raw = self.i2c.readfrom_mem(self.addr, 0xF7, 8)
-        raw_p = ((raw[0] << 16) | (raw[1] << 8) | raw[2]) >> 4
-        raw_t = ((raw[3] << 16) | (raw[4] << 8) | raw[5]) >> 4
-        raw_h = (raw[6] << 8) | raw[7]
-
-        # Temperature calculation (Celsius)
-        var1 = (((raw_t >> 3) - (self.dig_t1 << 1)) * self.dig_t2) >> 11
-        var2 = (
-            (((raw_t >> 4) - self.dig_t1) * ((raw_t >> 4) - self.dig_t1)) >> 12
-        ) * self.dig_t3 >> 14
-        t_fine = var1 + var2
-        temp = ((t_fine * 5 + 128) >> 8) / 100.0
-
-        # Pressure calculation (hPa)
-        p_var1 = t_fine - 128000
-        p_var2 = (
-            p_var1 * p_var1 * self.dig_p6 + ((p_var1 * self.dig_p5) << 17) + (self.dig_p4 << 35)
-        )
-        p_var1 = ((p_var1 * p_var1 * self.dig_p3) >> 8) + ((p_var1 * self.dig_p2) << 12)
-        p_var1 = (((1 << 47) + p_var1) * self.dig_p1) >> 33
-
-        if p_var1 == 0:
-            pressure = 0.0
-        else:
-            p = 1048576 - raw_p
-            p = (((p << 31) - p_var2) * 3125) // p_var1
-            p_var1 = (self.dig_p9 * (p >> 13) * (p >> 13)) >> 25
-            p_var2 = (self.dig_p8 * p) >> 19
-            p = ((p + p_var1 + p_var2) >> 8) + (self.dig_p7 << 4)
-            pressure = (p / 256.0) / 100.0
-
-        # Humidity calculation (%)
-        h_var = t_fine - 76800
-        h_var = ((((raw_h << 14) - (self.dig_h4 << 20) - (self.dig_h5 * h_var)) + 16384) >> 15) * (
-            (
-                (
-                    (
-                        (((h_var * self.dig_h6) >> 10) * (((h_var * self.dig_h3) >> 11) + 32768))
-                        >> 10
-                    )
-                    + 2097152
-                )
-                * self.dig_h2
-                + 8192
-            )
-            >> 14
-        )
-        h_var = h_var - (((((h_var >> 15) * (h_var >> 15)) >> 7) * self.dig_h1) >> 4)
-        h_var = max(0, min(h_var, 419430400))
-        humidity = (h_var >> 12) / 1024.0
-
-        return {
-            "temperature": round(temp, 2),
-            "pressure": round(pressure, 2),
-            "humidity": round(humidity, 2),
-        }
+# Dynamic sensor driver import
+if SENSOR_TYPE == "sht41":
+    from sht41 import SHT41
+elif SENSOR_TYPE == "bme280":
+    from bme280 import BME280
+else:
+    raise ValueError(f"Unsupported SENSOR_TYPE '{SENSOR_TYPE}'. Use 'bme280' or 'sht41'.")
 
 
 # -------------------------------------------------------------
 # Home Assistant MQTT Discovery
 # -------------------------------------------------------------
-def register_ha_discovery(mqtt):
-    # Device naming uses NODE_NAME so each board has its own clean device card in HA
-    device_info = (
-        f'"device":{{'
-        f'"identifiers":["{Config.NODE_ID}"],'
-        f'"name":"{NODE_NAME}",'
-        f'"model":"Pico 2 W",'
-        f'"manufacturer":"Raspberry Pi"'
-        f"}}"
-    )
+def register_ha_discovery(mqtt, sensor_type):
+    device_info = {
+        "identifiers": [Config.NODE_ID],
+        "name": NODE_NAME,
+        "model": f"Pico 2 W ({sensor_type.upper()})",
+        "manufacturer": "Raspberry Pi",
+    }
 
     configs = [
         {
@@ -231,35 +54,39 @@ def register_ha_discovery(mqtt):
             "cls": "humidity",
             "val_tpl": "{{ value_json.humidity }}",
         },
-        {
-            "id": "pressure",
-            "name": "Pressure",
-            "unit": "hPa",
-            "cls": "atmospheric_pressure",
-            "val_tpl": "{{ value_json.pressure }}",
-        },
     ]
 
+    if sensor_type == "bme280":
+        configs.append(
+            {
+                "id": "pressure",
+                "name": "Pressure",
+                "unit": "hPa",
+                "cls": "atmospheric_pressure",
+                "val_tpl": "{{ value_json.pressure }}",
+            }
+        )
+
     for c in configs:
         topic = f"homeassistant/sensor/{Config.NODE_ID}/{c['id']}/config"
-        unique_id = f"{Config.NODE_ID}_{c['id']}"
-        payload = (
-            f'{{"name":"{c["name"]}",'
-            f'"has_entity_name":true,'
-            f'"unique_id":"{unique_id}",'
-            f'"device_class":"{c["cls"]}",'
-            f'"state_class":"measurement",'
-            f'"unit_of_measurement":"{c["unit"]}",'
-            f'"state_topic":"{STATE_TOPIC}",'
-            f'"value_template":"{c["val_tpl"]}",'
-            f"{device_info}}}"
-        )
-        mqtt.publish(topic, payload, retain=True)
+        payload = {
+            "name": c["name"],
+            "has_entity_name": True,
+            "unique_id": f"{Config.NODE_ID}_{c['id']}",
+            "device_class": c["cls"],
+            "state_class": "measurement",
+            "unit_of_measurement": c["unit"],
+            "state_topic": STATE_TOPIC,
+            "value_template": c["val_tpl"],
+            "device": device_info,
+        }
+
+        mqtt.publish(topic, json.dumps(payload), retain=True)
         print(f"Registered HA discovery: {c['id']}")
 
 
 # -------------------------------------------------------------
-# Instantiate Wi-Fi connection
+# Wi-Fi Connection
 # -------------------------------------------------------------
 def connect_wifi():
     wlan = network.WLAN(network.STA_IF)
@@ -278,10 +105,9 @@ def connect_wifi():
 
 
 # -------------------------------------------------------------
-# Panic when the sensor isn't ready
+# Panic Handler
 # -------------------------------------------------------------
 def panic(err=None):
-    """Signals a fatal fault by blinking the onboard LED continuously."""
     if err:
         print(f"Fatal error: {err}")
     led = Pin("LED", Pin.OUT)
@@ -294,9 +120,14 @@ def panic(err=None):
 # Main Execution Loop
 # -------------------------------------------------------------
 def main():
-    # Adjust SDA/SCL pins according to your wiring
-    i2c = SoftI2C(sda=Pin(16), scl=Pin(17), freq=100000)
-    bme = BME280(i2c)
+    i2c = SoftI2C(sda=Pin(4), scl=Pin(5), freq=100000)
+
+    if SENSOR_TYPE == "sht41":
+        print("Using SHT41 sensor (0x44)")
+        sensor = SHT41(i2c)
+    else:
+        print("Using BME280 sensor (0x77)")
+        sensor = BME280(i2c)
 
     connect_wifi()
 
@@ -309,19 +140,16 @@ def main():
     mqtt.connect(Config.CLIENT_ID, mqtt_user, mqtt_pass)
     print("MQTT connected.")
 
-    # Publish discovery retained messages
-    register_ha_discovery(mqtt)
+    register_ha_discovery(mqtt, SENSOR_TYPE)
 
-    # Telemetry loop
     interval = getattr(Config, "UPDATE_INTERVAL", 30)
     while True:
         try:
-            data = bme.read_values()
-            state_json = (
-                f'{{"temperature":{data["temperature"]},'
-                f'"humidity":{data["humidity"]},'
-                f'"pressure":{data["pressure"]}}}'
-            )
+            data = sensor.read_values()
+
+            payload = {k: v for k, v in data.items() if v is not None}
+            state_json = json.dumps(payload)
+
             mqtt.publish(STATE_TOPIC, state_json)
             print(f"[{NODE_NAME}] Published: {state_json}")
         except Exception as e:
@@ -338,10 +166,7 @@ def main():
 
 
 if __name__ == "__main__":
-    # Allow 3.3V power rails and I2C registers to settle on cold boot
     time.sleep(2)
-
-    # Indicate startup has begun
     Pin("LED", Pin.OUT).on()
 
     try:

package.json

@@ -0,0 +1,5 @@
+{
+  "deps": [
+    ["ssd1306", "0.1.0"]
+  ]
+}

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "pico-thermo"
-version = "0.1.1"
+version = "0.2.0"
 description = "MicroPython MQTT app to read BME280 sensor into Home Assistant"
 readme = "README.md"
 requires-python = ">=3.9"
@@ -9,7 +9,7 @@ authors = [
 ]
 
 [tool.ruff]
-target-version = "py311"
+target-version = "py312"
 line-length = 100
 
 [tool.ruff.lint]