diff --git a/frappy_psi/drums.py b/frappy_psi/drums.py
index b06da48..650ddcc 100644
--- a/frappy_psi/drums.py
+++ b/frappy_psi/drums.py
@@ -56,7 +56,7 @@ class Drums(Writable):
             self._pos = 0
         for i, action in enumerate(self.pattern[self._pos:]):
             upper = action.upper()
-            relais = self.actions.get(action.upper())
+            relais = self.actions.get(upper)
             if relais:
                 relais.write_target(upper == action)  # True when capital letter
             else:
diff --git a/frappy_psi/ionopimax.py b/frappy_psi/ionopimax.py
index f43871a..e9a9e45 100644
--- a/frappy_psi/ionopimax.py
+++ b/frappy_psi/ionopimax.py
@@ -18,16 +18,39 @@
 #   Jael Celia Lorenzana <jael-celia.lorenzana@psi.ch>
 # *****************************************************************************
 
+import os
+from glob import glob
 from frappy.core import Readable, Writable, Parameter, BoolType, StringType,\
     FloatRange, Property, TupleOf, ERROR, IDLE
+from frappy.errors import ConfigError
 from math import log
 
+basepaths = '/sys/class/ionopimax', '/sys/class/ionopi'
+
 
 class Base:
     addr = Property('address', StringType())
+    _devpath = None
+    devclass = None
+
+    def initModule(self):
+        super().initModule()
+        # candidates = glob(f'/sys/class/iono*/*/{self.addr}')
+        # if not candidates:
+        #     raise ConfigError(f'can not find path for {self.addr}')
+        for basepath in basepaths:
+            for devclass in ([self.devclass] if isinstance(self.devclass, str) else self.devclass):
+                devpath = f'{basepath}/{devclass}'
+                if os.path.exists(devpath):
+                    self._devpath = devpath
+                    return
+                else:
+                    self.log.info('%s does not exist', devpath)
+        else:
+            raise ConfigError(f'device path for {self.devclass} not found {devpath}')
 
     def read(self, addr, scale=None):
-        with open(f'/sys/class/ionopimax/{self.devclass}/{addr}') as f:
+        with open(f'{self._devpath}/{addr}') as f:
             result = f.read()
         if scale:
             return float(result) / scale
@@ -35,7 +58,7 @@ class Base:
 
     def write(self, addr, value, scale=None):
         value = str(round(value * scale)) if scale else str(value)
-        with open(f'/sys/class/ionopimax/{self.devclass}/{addr}', 'w') as f:
+        with open(f'{self._devpath}/{addr}', 'w') as f:
             f.write(value)
 
 
@@ -49,7 +72,7 @@ class DigitalInput(Base, Readable):
 
 class DigitalOutput(DigitalInput, Writable):
     target = Parameter('output state', BoolType(), readonly=False)
-    devclass = 'digital_out'
+    devclass = 'digital_out', 'relay'
 
     def write_target(self, value):
         self.write(self.addr, value, 1)