Implement HAL and apply macros across code-base

Implement AVR Platform

Marlin/src/HAL/HAL_endstop_interrupts.h

@@ -0,0 +1,53 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+
+#ifndef HAL_ENDSTOP_INTERRUPTS_H_
+#define HAL_ENDSTOP_INTERRUPTS_H_
+
+volatile uint8_t e_hit = 0; // Different from 0 when the endstops should be tested in detail.
+                            // Must be reset to 0 by the test function when finished.
+
+// This is what is really done inside the interrupts.
+FORCE_INLINE void endstop_ISR_worker( void ) {
+  e_hit = 2; // Because the detection of a e-stop hit has a 1 step debouncer it has to be called at least twice.
+}
+
+// One ISR for all EXT-Interrupts
+void endstop_ISR(void) { endstop_ISR_worker(); }
+
+#ifdef ARDUINO_ARCH_AVR
+
+  #include "HAL_AVR/endstop_interrupts.h"
+
+#elif defined(ARDUINO_ARCH_SAM)
+
+  #include "HAL_DUE/endstop_interrupts.h"
+
+#elif IS_32BIT_TEENSY
+
+  #include "HAL_TEENSY35_36/endstop_interrupts.h"
+
+#else
+
+  #error Unsupported Platform!
+
+#endif
+
+#endif /* HAL_ENDSTOP_INTERRUPTS_H_ */