Added script query_device.py

tests/sensor.py

@@ -1,14 +1,21 @@
+import minimalmodbus
+import serial
+import time
+
 class Sensor():
-    baudrate_config = [ 19200,4800,9600,14400,19200,28800,38400,57600,76800,115200 ]
+    holding_register_start = 40001
+    holding_register_end = 49999
+    input_register_start = 30001
+    input_register_end = 39999
     baudrates = [ 4800,9600,14400,19200,28800,38400,57600,76800,115200 ]
     input_register_offset = { \
-            'CO2_addr': 9, \
-            'T_SHT4x_addr': 10, \
-            'RH_SHT4x_addr': 11, \
-            'T_SCD4x_addr': 12, \
-            'RH_SCD4x_addr': 13, \
-            'T_SHT4x_signed_addr': 14, \
-            'T_SCD4x_signed_addr': 15 }
+            'CO2': 9, \
+            'T_SHT4x': 10, \
+            'RH_SHT4x': 11, \
+            'T_SCD4x': 12, \
+            'RH_SCD4x': 13, \
+            'T_SHT4x_signed': 14, \
+            'T_SCD4x_signed': 15 }
     holding_register_offset = { \
             'LED_on_register': 0, \
             'LED_brightness_register': 1, \
@@ -18,3 +25,76 @@ class Sensor():
             'SCD4x_temperature_offset_register': 5, \
             'MODBUS_address_register': 6, \
             'baudrate_register': 7 }
+    def __init__(self, dev_file='/dev/rs485', address=247, baudrate=19200):
+        self.dev_file = dev_file
+        self.address = address
+        self.baudrate = baudrate
+        self.open()
+    def open(self):
+        self.serial = minimalmodbus.Instrument(self.dev_file, self.address, close_port_after_each_call=True)
+        self.serial.serial.baudrate = self.baudrate
+        self.serial.serial.bytesize = 8
+        self.serial.serial.parity   = serial.PARITY_EVEN
+        self.serial.serial.stopbits = 1
+        self.serial.serial.timeout  = 0.05          # seconds
+        self.serial.mode = minimalmodbus.MODE_RTU   # rtu or ascii mode
+        self.serial.clear_buffers_before_each_transaction = True
+    def close(self):
+        self.serial.serial.close()
+        self.serial = None
+    # High level read functions
+    @property
+    def CO2(self):
+        return self.read_input_register(self.input_register_offset['CO2'])*10
+    @property
+    def T(self):
+        # TODO maybe use rather signed version?
+        return self.T_SHT4x
+    @property
+    def RH(self):
+        return self.RH_SHT4x
+    @property
+    def T_SHT4x(self):
+        return self.read_input_register(self.input_register_offset['T_SHT4x'])
+    @property
+    def T_SHT4x_signed(self):
+        return self.read_input_register(self.input_register_offset['T_SHT4x_signed'], signed=True)
+    @property
+    def RH_SHT4x(self):
+        return self.read_input_register(self.input_register_offset['RH_SHT4x'])*10
+    @property
+    def T_SCD4x(self):
+        return self.read_input_register(self.input_register_offset['T_SCD4x'])
+    @property
+    def T_SCD4x_signed(self):
+        return self.read_input_register(self.input_register_offset['T_SCD4x_signed'], signed=True)
+    @property
+    def RH_SCD4x(self):
+        return self.read_input_register(self.input_register_offset['RH_SCD4x'])*10
+    def read_input_register(self, register_offset):
+        retries = 10
+        while retries:
+            try:
+                return self.serial.read_register(register_offset, 1, functioncode=4)
+            except (minimalmodbus.NoResponseError, minimalmodbus.InvalidResponseError) as e:
+                retries -= 1
+                continue
+        raise e
+    # generic read register function
+    def read_register(self, register_number):
+        if self.input_register_start <= register_number <= self.input_register_end:
+            function_code = 4
+            register_offset = register_number - self.input_register_start
+        elif self.holding_register_start <= register_number <= self.holding_register_end:
+            function_code = 3
+            register_offset = register_number - self.holding_register_start
+        else:
+            # wrong register number
+            raise ValueError
+        return self.serial.read_register(register_offset, 1, functioncode=function_code) * 10
+    def write_register(self, register_number, register_value):
+        if not self.holding_register_start <= register_number <= self.holding_register_end:
+            raise ValueError
+        register_offset = register_number - self.holding_register_start
+        return self.serial.write_register(register_offset, register_value, functioncode=6)
+