add comment that i_data and o_data have to be added by user

diff --git a/src/add/singlepipe.py b/src/add/singlepipe.py
index 85cab6c73161825b6ce47d34c2a1caae494f9991..ff7f3ef3f2795b1cc7a6ca701da949571b35bcca 100644 (file)
--- a/src/add/singlepipe.py
+++ b/src/add/singlepipe.py
@@ -170,6 +170,7 @@ class PrevControl:
     def __init__(self, i_width=1):
         self.i_valid = Signal(i_width, name="p_i_valid") # prev   >>in  self
         self.o_ready = Signal(name="p_o_ready") # prev   <<out self
+        self.i_data = None # XXX MUST BE ADDED BY USER
 
     def _connect_in(self, prev):
         """ internal helper function to connect stage to an input source.
@@ -198,6 +199,7 @@ class NextControl:
     def __init__(self):
         self.o_valid = Signal(name="n_o_valid") # self out>>  next
         self.i_ready = Signal(name="n_i_ready") # self <<in   next
+        self.o_data = None # XXX MUST BE ADDED BY USER
 
     def connect_to_next(self, nxt):
         """ helper function to connect to the next stage data/valid/ready.