From aaeadf0cbd95b532d5d2cee482c53c238a8f5e12 Mon Sep 17 00:00:00 2001
From: Scott Lahteine <sourcetree@thinkyhead.com>
Date: Wed, 11 May 2016 15:29:54 -0700
Subject: [PATCH] If no "B" parameter given, get 1 byte

---
 Marlin/Marlin_main.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Marlin/Marlin_main.cpp b/Marlin/Marlin_main.cpp
index 10d26ac98b..99786e6170 100644
--- a/Marlin/Marlin_main.cpp
+++ b/Marlin/Marlin_main.cpp
@@ -5038,7 +5038,7 @@ inline void gcode_M121() { endstops.enable_globally(false); }
    */
   inline void gcode_M156() {
     uint8_t addr = code_seen('A') ? code_value_short() : 0;
-    int bytes    = code_seen('B') ? code_value_short() : 0;
+    int bytes    = code_seen('B') ? code_value_short() : 1;
 
     if (addr && bytes > 0 && bytes <= 32) {
       i2c.address(addr);