added lakeshore temperature controller

src/damaris/tools/lakeshore.py

@@ -0,0 +1,108 @@
+import serial
+import re
+import operator
+import numpy as np
+
+
+DEBUG = False
+
+reply_pattern = re.compile(r"\x02..(.*)\x03.", re.DOTALL)
+# example answer '\x02PV279.8\x03/'
+# [EOT] = \x04
+# [STX] = \x02
+# [ENQ] = \x05
+# [ETX] = \x03
+# [ACK] = \x06
+# BCC = checksum
+
+standard_device = '/dev/ttyUSB0'
+#EOT = '\x04'
+#STX = '\x02'
+#ENQ = '\x05'
+#ETX = '\x03'
+#ACK = '\x06'
+#NAK = '\x15'
+
+
+"""
+Parameter read example:
+
+Master: [EOT]0011PV[ENQ]
+Instrument: [STX]PV16.4[ETX]{BCC}
+
+Writing data:
+
+Master: [EOT] {GID}{GID}{UID}{UID}[STX]{CHAN}(c1)(c2)<DATA>[ETX](BCC)
+
+"""
+
+
+
+class Lakeshore(object):
+    def __init__(self, serial_device, baudrate=57600):
+        self.device = standard_device
+        # timeout: 110 ms to get all answers.
+        self.s = serial.Serial(serial_device,
+                               baudrate=baudrate,
+                               bytesize=7,
+                               parity='O',
+                               stopbits=1,
+                               timeout=0.4)
+        self._expect_len = 50
+
+    def __del__(self):
+        self.s.close()
+
+    #def get_current_temperature(self):  # Temp A
+     #   self.s.write("KRDG? a\n")
+     #  a = self.s.readline().strip()[1:]
+     #   return float(a)
+
+    def get_temperature_A(self):  # Temp A
+        self.s.write("KRDG? a\n")
+        a = self.s.readline().strip()[1:]
+        return float(a)
+
+    def get_temperature_B(self):  # Temp B
+        self.s.write("KRDG? b\n")
+        b = self.s.readline().strip()[1:]
+        return float(b)
+
+    def set_temperature(self, temperature):     # setze Setpoint
+        t = temperature
+        self.s.write(f"SETP 1,{t}\n")
+
+    def set_ramp(self, ramp):
+        return self.s.write(f'RAMP 1, 1, {ramp}\n')
+        
+    def get_set_temperature(self):      # Setpoint abfrage
+        self.s.write("SETP? 1\n")
+        s = self.s.readline().strip()[1:]
+        return float(s)
+
+    def get_output(self):               # Heater Output
+        self.s.write("HTR? 1\n")
+        o = self.s.readline().strip()[1:]
+        return float(o)
+
+    def get_ramp(self):
+        self.s.write('RAMP? 1\n')
+        ret = self.s.readline().strip()
+        onoff, rate = ret.split(',')
+        if onoff:
+            return float(rate)
+        else:
+            return 0.0
+
+    def get_value(self, name):
+        temp = self.read_param(name)
+        if temp is None:
+            return np.nan
+        else:
+            try:
+                return float(temp)
+            except ValueError:
+                return np.nan
+
+    def close(self):
+        self.s.close()