No variable spindle and spindle speed fix.

- Soft limit errors were stuck in a feed hold without notifying the
user why it was in a hold. When resumed, the soft limit error would
kick in. Issue should be fixed to behave as intended to automatically
hold and issue a soft limit alarm once the machine has come to a stop.

doc/log/commit_log_v1.0c.txt

@@ -1,3 +1,14 @@
+----------------
+Date: 2016-03-11
+Author: Sonny Jeon
+Subject: Soft limit error bug fix.
+
+- Soft limit errors were stuck in a feed hold without notifying the
+user why it was in a hold. When resumed, the soft limit error would
+kick in. Issue should be fixed to behave as intended. To automatically
+hold and issue a soft limit alarm once the machine has come to a stop.
+
+
 ----------------
 Date: 2016-03-04
 Author: Sonny Jeon

grbl/grbl.h

@@ -23,7 +23,7 @@
 
 // Grbl versioning system
 #define GRBL_VERSION "1.0c"
-#define GRBL_VERSION_BUILD "20160311"
+#define GRBL_VERSION_BUILD "20160319"
 
 // Define standard libraries used by Grbl.
 #include <avr/io.h>

grbl/spindle_control.c

@@ -138,14 +138,13 @@ void spindle_set_state(uint8_t state, float rpm)
       
     #else
       
-      if (rpm <= 0.0) { spindle_stop(); } // RPM should never be negative, but check anyway.
-      else {
-        #ifdef INVERT_SPINDLE_ENABLE_PIN
-          SPINDLE_ENABLE_PORT &= ~(1<<SPINDLE_ENABLE_BIT);
-        #else
-          SPINDLE_ENABLE_PORT |= (1<<SPINDLE_ENABLE_BIT);
-        #endif
-      }
+     // NOTE: Without variable spindle, the enable bit should just turn on or off, regardless
+     // if the spindle speed value is zero, as its ignored anyhow.
+     #ifdef INVERT_SPINDLE_ENABLE_PIN
+       SPINDLE_ENABLE_PORT &= ~(1<<SPINDLE_ENABLE_BIT);
+     #else
+       SPINDLE_ENABLE_PORT |= (1<<SPINDLE_ENABLE_BIT);
+     #endif
       
     #endif