fs (and other furnaces): fixes on interlock

- try to make interlock right
- merge status where ever possbile

frappy_psi/picontrol.py

@@ -61,7 +61,7 @@ example cfg:
 import time
 import math
 from frappy.core import Readable, Writable, Parameter, Attached, IDLE, Property
-from frappy.lib import clamp
+from frappy.lib import clamp, merge_status
 from frappy.datatypes import LimitsType, EnumType, BoolType, FloatRange
 from frappy.ctrlby import HasOutputModule
 from frappy_psi.convergence import HasConvergence
@@ -94,7 +94,6 @@ class PImixin(HasOutputModule, Writable):
         if not self.control_active:
             return
         out = self.output_module
-        self.status = IDLE, 'controlling'
         now = time.time()
         deltat = clamp(0, now-self._lasttime, 10)
         self._lasttime = now
@@ -115,6 +114,12 @@ class PImixin(HasOutputModule, Writable):
             self._overflow = 0
         out.update_target(self.name, self._cvt2ext(output))
 
+    def read_status(self):
+        status = IDLE, 'controlling' if self.control_active else 'inactive'
+        if hasattr(super(), 'read_status'):
+            status = merge_status(super().read_status(), status)
+        return status
+
     def cvt2int_square(self, output):
         return (math.sqrt(max(0, clamp(x, *self._get_range()))) for x in (output, self.output_min, self.output_max))
 
@@ -146,10 +151,12 @@ class PImixin(HasOutputModule, Writable):
         self._cvt2int = getattr(self, f'cvt2int_{self.output_func.name}')
         self._cvt2ext = getattr(self, f'cvt2ext_{self.output_func.name}')
 
-    def write_control_active(self, value):
-        super().write_control_active(value)
-        if not value:
-            self.output_module.write_target(0)
+    # not needed, done by HasOutputModule.write_control_active
+    # def write_control_active(self, value):
+    #    super().write_control_active(value)
+    #    out = self.output_module
+    #    if not value:
+    #        out.write_target(out.parameters['target'].datatype.default)
 
     def set_target(self, value):
         if not self.control_active: