further simplification of the i800 code

1 files changed, 12 insertions, 11 deletions

diff --git a/qolab/hardware/i_server/i800.py b/qolab/hardware/i_server/i800.py
index e7b8dcb..7743d84 100644
--- a/qolab/hardware/i_server/i800.py
+++ b/qolab/hardware/i_server/i800.py
@@ -16,29 +16,30 @@ class I800(BasicInstrument):
         BasicInstrument.__init__(self, *args, **kwds)
         self.host=host
         self.port=port
+        self.modbus_address='01'
+        self.cmd_start_marker='*'
         self.config['Device type']='TemperatureController'
         self.config['Device model'] = 'i800'
         self.config['FnamePrefix'] = 'temperature'
         self.deviceProperties = {'Temperature'}
 
-    def query(self, qstr):
+    def query(self, cmnd):
+        modbus_cmnd = f'{self.modbus_address}{cmnd}'
+        qstr=f'POST / HTTP/1.1\r\n\r\n{self.cmd_start_marker}{modbus_cmnd}\r\n'
         s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
         s.connect((self.host, self.port))
         s.send(qstr.encode('ascii'))
-        return s.recv(100).decode('ascii')
+        reply = s.recv(100).decode('ascii')
+        if reply[0:5] != f'{modbus_cmnd}':
+            # check the proper echo response
+            return None
+        return reply[5:-1] # last symbol is '\r'
 
     @BasicInstrument.tsdb_append
     def getTemperature(self):
-        cmd_start_marker='*'
-        modbus_address='01' 
         command='X01'; # give decimal representation (X) of the temperature (01 address)
-        qstr=f'POST / HTTP/1.1\r\n\r\n{cmd_start_marker}{modbus_address}{command}\r\n'
-        reply=self.query(qstr)
-        if reply[0:5] != f'{modbus_address}{command}':
-            # check the proper echo response
-            return None
-        t = reply[5:]
-        t = float(t)
+        reply=self.query(command)
+        t = float(reply)
         return t