Power signal control definitions for ATX and others

Marlin/Configuration.h

 #define MOTHERBOARD 7
 #endif
 
+//// The following define selects which power supply you have. Please choose the one that matches your setup
+// 1 = ATX
+// 2 = X-Box 360 203Watts (the blue wire connected to PS_ON and the red wire to VCC)
 
+#define POWER_SUPPLY 1
 
 //===========================================================================
 //=============================Thermal Settings  ============================

Marlin/Configuration_adv.h

 #ifdef ULTIPANEL
  #undef SDCARDDETECTINVERTED
 #endif
+
+// Power Signal Control Definitions
+// By default use ATX definition
+#ifndef POWER_SUPPLY
+  #define POWER_SUPPLY 1
+#endif
+// 1 = ATX
+#if (POWER_SUPPLY == 1) 
+  #define PS_ON_AWAKE  LOW
+  #define PS_ON_ASLEEP HIGH
+#endif
+// 2 = X-Box 360 203W
+#if (POWER_SUPPLY == 2) 
+  #define PS_ON_AWAKE  HIGH
+  #define PS_ON_ASLEEP LOW
+#endif
+
 //===========================================================================
 //=============================Buffers           ============================
 //===========================================================================

Marlin/Marlin_main.cpp

     #if (PS_ON_PIN > -1)
       case 80: // M80 - ATX Power On
         SET_OUTPUT(PS_ON_PIN); //GND
-        WRITE(PS_ON_PIN, LOW);
+        WRITE(PS_ON_PIN, PS_ON_AWAKE);
         break;
       #endif
       
         suicide();
       #elif (PS_ON_PIN > -1)
         SET_OUTPUT(PS_ON_PIN); 
-        WRITE(PS_ON_PIN, HIGH);
+        WRITE(PS_ON_PIN, PS_ON_ASLEEP);
       #endif
 		break;