From 5e673e0c0edabaaf9a761404a42062d8800d0fca Mon Sep 17 00:00:00 2001
From: Maximilian Giller <m.giller.dev@gmail.com>
Date: Sat, 10 Aug 2024 02:50:05 +0200
Subject: [PATCH] Self implemented co2 again

---
 src/handler/mhz19_co2.py | 40 ++++++++++++++++++++++++++++++++++++----
 1 file changed, 36 insertions(+), 4 deletions(-)

diff --git a/src/handler/mhz19_co2.py b/src/handler/mhz19_co2.py
index 4ac99d7..bc28016 100644
--- a/src/handler/mhz19_co2.py
+++ b/src/handler/mhz19_co2.py
@@ -1,16 +1,48 @@
-import mh_z19
-import logging
+import serial
 
 
 class Mhz19Co2:
-
     def __init__(self):
         self.last_read = None
 
+        self.serial_port = "/dev/serial0"
+        self.baud_rate = 9600
+        self.byte_size = 8
+        self.parity = "N"
+        self.stop_bits = 1
+        self.timeout = None
+
     def get_last_read(self) -> int | None:
         if self.last_read is None:
             return self.read()
         return self.last_read
 
     def read(self) -> int | None:
-        return mh_z19.read()["co2"]
+        ser = None
+        try:
+            ser = serial.Serial(
+                port=self.serial_port,
+                baudrate=self.baud_rate,
+                bytesize=self.byte_size,
+                parity=self.parity,
+                stopbits=self.stop_bits,
+                timeout=self.timeout,
+            )
+
+            # send "Read CO2" command
+            command_data = bytes([0xFF, 0x01, 0x86, 0x00, 0x00, 0x00, 0x00, 0x00, 0x79])
+            ser.write(command_data)
+
+            # read "Return Value (CO2 concentration)"
+            data = ser.read(9)
+            concentration = data[2] * 256 + data[3]
+
+        except Exception as e:
+            print(f"Error reading data: {e}")
+        finally:
+            if ser:
+                ser.close()
+                ser = None
+
+        self.last_read = concentration
+        return concentration