frappy_psi.phytron: implement limit switches

frappy_psi/phytron.py

@@ -20,15 +20,12 @@
 #
 # *****************************************************************************
 
-"""driver for phytron motors
-
-limits switches are not yet implemented
-"""
+"""driver for phytron motors """
 
 import time
 from frappy.core import Done, Command, EnumType, FloatRange, IntRange, \
     HasIO, Parameter, Property, Drivable, PersistentMixin, PersistentParam, \
-    StringIO, StringType, IDLE, BUSY, ERROR, Limit
+    StringIO, StringType, IDLE, BUSY, ERROR, Limit, BoolType
 from frappy.errors import CommunicationFailedError, HardwareError
 from frappy.features import HasOffset
 from frappy.states import HasStates, status_code, Retry
@@ -66,6 +63,8 @@ class Motor(HasOffset, HasStates, PersistentMixin, HasIO, Drivable):
 
     encoder_mode = Parameter('how to treat the encoder', EnumType('encoder', NO=0, READ=1, CHECK=2),
                              default=1, readonly=False)
+    check_limit_switches = Parameter('whethter limit switches are checked',BoolType(),
+                                     default=0, readonly=False)
     value = PersistentParam('angle', FloatRange(unit='deg'))
     status = PersistentParam()
     target = Parameter('target angle', FloatRange(unit='deg'), readonly=False)
@@ -186,11 +185,14 @@ class Motor(HasOffset, HasStates, PersistentMixin, HasIO, Drivable):
                 self.hw_stop()
 
     def read_status(self):
+        hexstatus = 0x100
         for _ in range(3):
             sysstatus = self.communicate(f'{self.address:x}SE')
             try:
                 sysstatus = sysstatus[1:4] if self.axis == 'X' else sysstatus[5:8]
                 hexstatus = int(sysstatus, base=16)
+                if not self.check_limit_switches:
+                    hexstatus &= 0xfcf  # ignore limit switch bits
                 status_items = formatStatusBits(hexstatus & 0xf7, self.status_bits)
                 if status_items:
                     status = ERROR, ', '.join(status_items)