diff --git a/README.md b/README.md
index 266b8d0..eeae974 100644
--- a/README.md
+++ b/README.md
@@ -22,7 +22,7 @@ This uses an AVR microcontroller (ATMega328P-PU).
 
 | ID | Name     | Size | Layout |
 |-|-|-|-|
-| 0  | stop     | 1    | id (3) |
+| 0  | stop     | 1    | id (3), empty (5) |
 | 1  | setup    | 8    | id (3), us_per_tick (29), amplitude (8), size (24) |
 | 2  | set      | 3    | id (3), index (5), frequency (12), empty (4) |
 | 3  | set-ts   | 5    | id (3), index (5), ticks (20), frequency (12) |