From eefc25be91615c7533bd95ea3d57ae8642759dad Mon Sep 17 00:00:00 2001
From: Scott R Carlson <scottrcarlson@gmail.com>
Date: Fri, 27 Dec 2013 15:09:00 -0500
Subject: [PATCH] Hard Limits configured for active high.

Added the use of homing_dir_mask to homing_cycle
---
 config.h |  2 +-
 limits.c | 30 ++++++++++++++++++++++++++----
 2 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/config.h b/config.h
index 9df2677..1fce110 100644
--- a/config.h
+++ b/config.h
@@ -53,7 +53,7 @@
 // are reached. You will need to ensure that you have appropriate pull-down resistors on the
 // limit switch input pins, or that your hardware drives the pins low when they are open (non-
 // triggered).
-// #define LIMIT_SWITCHES_ACTIVE_HIGH
+#define LIMIT_SWITCHES_ACTIVE_HIGH
 
 // If homing is enabled, homing init lock sets Grbl into an alarm state upon power up. This forces
 // the user to perform the homing cycle (or override the locks) before doing anything else. This is
diff --git a/limits.c b/limits.c
index a9a7e29..f91cf56 100644
--- a/limits.c
+++ b/limits.c
@@ -87,7 +87,7 @@ ISR(LIMIT_INT_vect)
 // algorithm is written here. This also lets users hack and tune this code freely for
 // their own particular needs without affecting the rest of Grbl.
 // NOTE: Only the abort runtime command can interrupt this process.
-static void homing_cycle(uint8_t cycle_mask, bool pos_dir, bool invert_pin, float homing_rate) 
+static void homing_cycle(uint8_t cycle_mask, bool approach, bool invert_pin, float homing_rate) 
 {
   if (sys.execute & EXEC_RESET) { return; }
   uint8_t limit_state;
@@ -101,9 +101,31 @@ static void homing_cycle(uint8_t cycle_mask, bool pos_dir, bool invert_pin, floa
   if (target[X_AXIS] < settings.max_travel[Y_AXIS]) { target[X_AXIS] = settings.max_travel[Y_AXIS]; }
   if (target[X_AXIS] < settings.max_travel[Z_AXIS]) { target[X_AXIS] = settings.max_travel[Z_AXIS]; }
   target[X_AXIS] *= 2.0;
-  if (pos_dir) { target[X_AXIS] = -target[X_AXIS]; }
-  target[Y_AXIS] = target[X_AXIS];
-  target[Z_AXIS] = target[X_AXIS];
+  uint8_t pos_dir = settings.homing_dir_mask;
+  if (pos_dir >= 128) {
+    pos_dir = pos_dir - 128;
+    target[Z_AXIS] = target[X_AXIS]; 
+  }
+  else { target[Z_AXIS] = -target[X_AXIS]; }
+  if (!approach) { target[Z_AXIS] = target[Z_AXIS] * -1; }
+
+  if (pos_dir >= 64) {
+    pos_dir = pos_dir - 64;
+    target[Y_AXIS] = target[X_AXIS];
+  }
+  else { target[Y_AXIS] = -target[X_AXIS]; }
+  if (!approach) { target[Y_AXIS] = target[Y_AXIS] * -1; }
+
+if (pos_dir >= 32) {
+    pos_dir = pos_dir -32;
+    target[X_AXIS] = target[X_AXIS];
+  }
+  else { target[X_AXIS] = -target[X_AXIS]; }
+  if (!approach) { target[X_AXIS] = target[X_AXIS] * -1; }
+
+  //if (pos_dir) { target[X_AXIS] = -target[X_AXIS]; }
+  //target[Y_AXIS] = target[X_AXIS];
+  //target[Z_AXIS] = target[X_AXIS];
   homing_rate *= 1.7320; // [sqrt(N_AXIS)] Adjust so individual axes all move at homing rate.
 
   // Setup homing axis locks based on cycle mask.