Added comment

diff --git a/src/spec/iomux.py b/src/spec/iomux.py
index 83f22d174506c23a9a79f82ac8c94a600a38c895..d69e94ac994f4c48c752b675b10f55fd41d8c8d8 100644 (file)
--- a/src/spec/iomux.py
+++ b/src/spec/iomux.py
@@ -28,6 +28,11 @@ io_layout = (("i", 1),
              ("o", 1)
             )
 
+# This block produces an N-to-1 mux with N 3-bit bank ports and one pad port.
+# The bank ports are intended to be wired to peripheral functions,
+# while the pad port will connect to the I/O pad.
+# Each port has o/oe/i signals, and the bank signal is used to select
+# between the bank ports.
 class IOMuxBlockSingle(Elaboratable):
 
     def __init__(self, n_banks=4):