added lakeshore to temperature logging facility

pyproject.toml

@@ -20,6 +20,7 @@ dependencies = [
     "matplotlib >= 1.4.1, <= 3.6",
     "pyxdg",
     "PyGObject >= 3.14.0, <= 3.51.0",
+    "pyserial>=3.5",
 ]
 authors = [
   {name = "Achim Gädke"},

src/damaris/tools/lakeshore.py

@@ -2,6 +2,9 @@ import serial
 import re
 import operator
 import numpy as np
+from functools import reduce
+
+from .temperature import TemperatureController, register_controller
 
 
 DEBUG = False
@@ -15,13 +18,18 @@ reply_pattern = re.compile(r"\x02..(.*)\x03.", re.DOTALL)
 # [ACK] = \x06
 # BCC = checksum
 
-standard_device = '/dev/ttyUSB0'
+standard_device = '0011'
-#EOT = '\x04'
+EOT = '\x04'
-#STX = '\x02'
+STX = '\x02'
-#ENQ = '\x05'
+ENQ = '\x05'
-#ETX = '\x03'
+ETX = '\x03'
-#ACK = '\x06'
+ACK = '\x06'
-#NAK = '\x15'
+NAK = '\x15'
+
+
+def checksum(message):
+	bcc = (reduce(operator.xor, list(map(ord,message))))
+	return chr(bcc)
 
 
 """
@@ -38,7 +46,7 @@ Master: [EOT] {GID}{GID}{UID}{UID}[STX]{CHAN}(c1)(c2)<DATA>[ETX](BCC)
 
 
 
-class Lakeshore(object):
+class Lakeshore(TemperatureController):
     def __init__(self, serial_device, baudrate=57600):
         self.device = standard_device
         # timeout: 110 ms to get all answers.
@@ -51,6 +59,8 @@ class Lakeshore(object):
         self._expect_len = 50
 
     def __del__(self):
+        if hasattr(self, 's') and self.s is not None:
+            if self.s.is_open:
                 self.s.close()
 
     #def get_current_temperature(self):  # Temp A
@@ -104,5 +114,76 @@ class Lakeshore(object):
             except ValueError:
                 return np.nan
 
+    def send_read_param(self, param):
+        self.s.write(EOT + self.device + param + ENQ)
+
+    def read_param(self, param):
+        self.s.flushInput()
+        self.send_read_param(param)
+        answer = self.s.read(self._expect_len)
+        m = reply_pattern.search(answer)
+        if m is None:
+            # Reading _expect_len bytes was not enough...
+            answer += self.s.read(200)
+            m = reply_pattern.search(answer)
+        if m is not None:
+            self._expect_len = len(answer)
+            return m.group(1)
+        else:
+            print("received:", repr(answer))
+            return None
+
+    def write_param(self, mnemonic, data):
+        if len(mnemonic) > 2:
+            raise ValueError
+        bcc = checksum(mnemonic + data + ETX)
+        mes = EOT+self.device+STX+mnemonic+data+ETX+bcc
+        if DEBUG:
+            for i in  mes:
+                print(i,hex(ord(i)))
+        self.s.flushInput()
+        self.s.write(mes)
+        answer = self.s.read(1)
+        # print "received:", repr(answer)
+        if answer == "":
+            # raise IOError("No answer from device")
+            return None
+        return answer[-1] == ACK
+
+    # TemperatureController interface implementation
+
+    def get_temperature(self) -> float:
+        """Read current temperature in Celsius."""
+        temp = self.get_temperature_A()
+        if temp is None:
+            return 0.0
+        try:
+            return float(temp)
+        except (ValueError, TypeError):
+            return 0.0
+
+    def get_setpoint(self) -> float:
+        """Read target setpoint temperature in Celsius."""
+        temp = self.get_set_temperature()
+        if temp is None:
+            return 0.0
+        try:
+            return float(temp)
+        except (ValueError, TypeError):
+            return 0.0
+
+    def set_setpoint(self, temperature: float) -> bool:
+        """Set target temperature in Celsius."""
+        self.set_temperature(temperature)
+        return True
+
     def close(self):
+        """Close the serial connection."""
+        if hasattr(self, 's') and self.s is not None:
+            if self.s.is_open:
                 self.s.close()
+            self.s = None
+
+
+# Register Lakeshore with the factory
+register_controller('lakeshore', Lakeshore)

src/damaris/tools/temperature.py

@@ -44,6 +44,7 @@ def create_controller(name: str, *args, **kwargs):
         module_map = {
             'simulated': 'damaris.tools.temperature_simulator',
             'eurotherm': 'damaris.tools.eurotherm',
+            'lakeshore': 'damaris.tools.lakeshore',
         }
         if name in module_map:
             try:
@@ -79,6 +80,13 @@ except ImportError as e:
     # That's OK, it will be imported on-demand if needed
     pass
 
+try:
+    from . import lakeshore
+except ImportError as e:
+    # Lakeshore may require serial module which might not be installed
+    # That's OK, it will be imported on-demand if needed
+    pass
+
 try:
     from . import temperature_simulator
 except ImportError as e: