Add G-code "backspace" support

4 years ago · ca5a8ea827
1 changed files with 9 additions and 3 deletions
--- a/Marlin/src/gcode/queue.cpp
+++ b/Marlin/src/gcode/queue.cpp
@ -387,9 +387,15 @@ inline void process_stream_char(const char c, uint8_t &sis, char (&buff)[MAX_CMD
    }
  #endif

-  buff[ind++] = c;
-  if (ind >= MAX_CMD_SIZE - 1)
-    sis = PS_EOL;               // Skip the rest on overflow
+  // Backspace erases previous characters
+  if (c == 0x08) {
+    if (ind) buff[--ind] = '\0';
+  }
+  else {
+    buff[ind++] = c;
+    if (ind >= MAX_CMD_SIZE - 1)
+      sis = PS_EOL;             // Skip the rest on overflow
+  }
 }

 /**