added drivers for small furnace

frappy_psi/furnace.py

@@ -0,0 +1,49 @@
+# *****************************************************************************
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free Software
+# Foundation; either version 2 of the License, or (at your option) any later
+# version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+# details.
+#
+# You should have received a copy of the GNU General Public License along with
+# this program; if not, write to the Free Software Foundation, Inc.,
+# 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+#
+# Module authors:
+#   Markus Zolliker <markus.zolliker@psi.ch>
+# *****************************************************************************
+
+"""interlocks for furnance"""
+
+import time
+from frappy.core import Module, Writable, Attached, Parameter, FloatRange, Readable, BoolType, ERROR, IDLE
+
+class Interlocks(Module):
+    input = Attached(Readable, 'the input module')
+    vacuum = Attached (Readable, 'the vacuum pressure')
+    wall_T = Attached (Readable, 'the wall temperature')
+    control = Attached(Module, 'the control module')
+    relais = Attached(Writable, 'the interlock relais')
+    wall_limit = Parameter('maximum wall temperature', FloatRange(0, unit='degC'),
+                           default = 50, readonly = False)
+    vacuum_limit = Parameter('maximum vacuum pressure', FloatRange(0, unit='mbar'),
+                             default = 0.1, readonly = False)
+    
+    def doPoll(self):
+        super().doPoll()
+        if self.input.status[0] >= ERROR:
+            self.control.status = self.input.status
+        elif self.vacuum.value > self.vacuum_limit:
+            self.control.status = ERROR, 'bad vacuum'
+        elif self.wall_T.value > self.wall_limit:
+            self.control.status = ERROR, 'wall overheat'
+        else:
+            return
+        self.control.write_control_active(False)
+        self.relais.write_target(False)
+        
+