[WIP] fi furnace improvements

- still under development

Change-Id: I5fc22f041fb136b549016f510f06ea703122bee5

frappy_psi/furnace.py

@@ -19,9 +19,9 @@
 
 """interlocks for furnace"""
 
-import time
 from frappy.core import Module, Writable, Attached, Parameter, FloatRange, Readable,\
      BoolType, ERROR, IDLE
+from frappy.errors import ImpossibleError
 from frappy.mixins import HasControlledBy
 from frappy_psi.picontrol import PImixin
 from frappy_psi.convergence import HasConvergence
@@ -30,15 +30,19 @@ import frappy_psi.tdkpower as tdkpower
 import frappy_psi.bkpower as bkpower
 
 
-class Interlocks(Module):
-    input = Attached(Readable, 'the input module')
-    vacuum = Attached(Readable, 'the vacuum pressure')
-    wall_T = Attached(Readable, 'the wall temperature')
-    htr_T = Attached(Readable, 'the heater temperature')
+class Interlocks(Writable):
+    value = Parameter('interlock o.k.', BoolType(), default=True)
+    target = Parameter('set to true to confirm', BoolType(), readonly=False)
+    input = Attached(Readable, 'the input module', mandatory=False)  # TODO: remove
+    vacuum = Attached(Readable, 'the vacuum pressure', mandatory=False)
+    wall_T = Attached(Readable, 'the wall temperature', mandatory=False)
+    htr_T = Attached(Readable, 'the heater temperature', mandatory=False)
     main_T = Attached(Readable, 'the main temperature')
     extra_T = Attached(Readable, 'the extra temperature')
     control = Attached(Module, 'the control module')
-    relais = Attached(Writable, 'the interlock relais')
+    htr = Attached(Module, 'the heater module', mandatory=False)
+    relais = Attached(Writable, 'the interlock relais', mandatory=False)
+    flowswitch = Attached(Readable, 'the flow switch', mandatory=False)
     wall_limit = Parameter('maximum wall temperature', FloatRange(0, unit='degC'),
                            default = 50, readonly = False)
     vacuum_limit = Parameter('maximum vacuum pressure', FloatRange(0, unit='mbar'),
@@ -46,9 +50,12 @@ class Interlocks(Module):
     htr_T_limit = Parameter('maximum htr temperature', FloatRange(0, unit='degC'),
                             default = 530, readonly = False)
     main_T_limit = Parameter('maximum main temperature', FloatRange(0, unit='degC'),
-                            default = 530, readonly = False)
+                             default = 530, readonly = False)
     extra_T_limit = Parameter('maximum extra temperature', FloatRange(0, unit='degC'),
-                            default = 530, readonly = False)
+                             default = 530, readonly = False)
+
+    _off_reason = None  # reason triggering interlock
+    _conditions = ''  # summary of reasons why locked now
 
     def initModule(self):
         super().initModule()
@@ -60,25 +67,50 @@ class Interlocks(Module):
             (self.vacuum, 'vacuum_limit'),
         ]
 
-    def doPoll(self):
-        # TODO: check channels are valid
-        super().doPoll()
-        newstatus = None
-        if self.input.status[0] >= ERROR:
-            newstatus = self.input.status
-        else:
-            for sensor, limitname in self._sensor_checks:
-                if sensor.value > getattr(self, limitname):
-                    newstatus = f'above {sensor.name} limit'
-                    break
-                if sensor.status[0] >= ERROR:
-                    newstatus = f'error at {sensor.name}: {sensor.status[1]}'
-            return
-        self.control.status = newstatus
+    def write_target(self, value):
+        if value:
+            self.read_status()
+            if self._conditions:
+                raise ImpossibleError('not ready to start')
+            self._off_reason = None
+            self.value = True
+        elif self.value:
+            self.switch_off()
+            self._off_reason = 'switched off'
+            self.value = False
+        self.read_status()
+
+    def switch_off(self):
+        if self.value:
+            self._off_reason = self._conditions
+            self.value = False
         if self.control.control_active:
             self.log.error('switch control off %r', self.control.status)
-        self.control.write_control_active(False)
-        self.relais.write_target(False)
+            self.control.write_control_active(False)
+            self.control.status = ERROR, self._conditions
+        if self.htr and self.htr.target:
+            self.htr.write_target(0)
+        if self.relais and (self.relais.value or self.relais.target):
+            self.relais.write_target(False)
+
+    def read_status(self):
+        conditions = []
+        if self.flowswitch and self.flowswitch.value == 0:
+            conditions.append('no cooling water')
+        for sensor, limitname in self._sensor_checks:
+            if sensor is None:
+                continue
+            if sensor.value > getattr(self, limitname):
+                conditions.append(f'above {sensor.name} limit')
+            if sensor.status[0] >= ERROR:
+                conditions.append(f'error at {sensor.name}: {sensor.status[1]}')
+                break
+        self._conditions = ', '.join(conditions)
+        if conditions and (self.control.control_active or self.htr.target):
+            self.switch_off()
+        if self.value:
+            return IDLE, '; '.join(conditions)
+        return ERROR, self._off_reason
 
 
 class PI(HasConvergence, PImixin):
@@ -111,3 +143,4 @@ class PKRgauge(LogVoltageInput):
     rawrange = (1.82, 8.6)
     valuerange = (5e-9, 1000)
     extendedrange = (0.5, 9.5)
+    value = Parameter(unit='mbar')