diff --git a/Makefile b/Makefile
index f0e70c8..cfa109f 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@ SLUG = rcm
 
 # Must follow the format in the Versioning section of
 # https://vcvrack.com/manual/PluginDevelopmentTutorial.html
-VERSION = 0.6.5
+VERSION = 0.6.6
 
 # FLAGS will be passed to both the C and C++ compiler
 #FLAGS += -Idep/openmpt-libopenmpt-0.3.10/soundlib -Idep/openmpt-libopenmpt-0.3.10/common
diff --git a/README.md b/README.md
index 7b7002e..e3990d0 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,21 @@
 
 # RCM plugins
 
+## Piano Roll
+
+*early version - forward compatibility not 100% guaranteed*
+
+A monophonic quantized sequencer. With `1v/oct`, `gate`, `retrigger` & `velocity` outputs. 64 patterns with up to 16 measures per pattern, up to 16 beats per measure and up to 16 divisions per beat. `EOP` will trigger when the last note in the pattern has been triggered. Patterns always loop (currently).
+
+Controls:
+
+* Left click a cell to activate that note.
+* Right click an active note to cause it to retrigger.
+* Hold down shift then drag a note up & down to alter the velocity, when dragging, press ctrl for more fine-grained control.
+* Use the panel on the right to alter the current pattern and its make-up.
+* Send a pulse to clock-in to advance each step (no internal clock).
+* Send a pulse to reset to prepare to play the current pattern from the start (plays 1st note on receiving first clock).
+
 ## Reverb
 
 Based on the GVerb GPL'd reverb code.