Merge pull request #3738 from thinkyhead/rc_limit_i2c_request

Print an error on bad i2c request
9 years ago · 675e92ab1f
parent a42655b9ac aaeadf0cbd
commit 675e92ab1f
1 changed files with 6 additions and 2 deletions
--- a/Marlin/Marlin_main.cpp
+++ b/Marlin/Marlin_main.cpp
@ -5038,12 +5038,16 @@ 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) {
+    if (addr && bytes > 0 && bytes <= 32) {
      i2c.address(addr);
      i2c.reqbytes(bytes);
    }
+    else {
+      SERIAL_ERROR_START;
+      SERIAL_ERRORLN("Bad i2c request");
+    }
  }

 #endif //EXPERIMENTAL_I2CBUS