diff --git a/protocol.md b/protocol.md
index 9a8c4c0..709d3da 100644
--- a/protocol.md
+++ b/protocol.md
@@ -19,7 +19,7 @@ Two wire UART 115200 8n1
 #### Packet
 55 AA bLen bAddr bCmd bArg bPayload[bLen-2] wChecksumLE
 
-* bLen - length of <bCmd bParam bPayload[]> part (length of payload minus 2)
+* bLen - length of <bCmd bArg bPayload[]> part (length of payload plus 2)
 * bAddr:
   * 0x20 - request to ESC
   * 0x21 - request to BLE