Add configuration store struct.

Firmware/ConfigurationStore.cpp

@@ -239,6 +239,41 @@ void Config_PrintSettings(uint8_t level)
 
 
 #ifdef EEPROM_SETTINGS
+
+static_assert (EXTRUDERS == 1, "ConfigurationStore M500_conf not implemented for more extruders.");
+static_assert (NUM_AXIS == 4, "ConfigurationStore M500_conf not implemented for more axis.");
+typedef struct
+{
+    char version[4];
+    float axis_steps_per_unit[4];
+    float max_feedrate_normal[4];
+    unsigned long max_acceleration_units_per_sq_second_normal[4];
+    float acceleration;
+    float retract_acceleration;
+    float minimumfeedrate;
+    float mintravelfeedrate;
+    unsigned long minsegmenttime;
+    float max_jerk[4];
+    float add_homing[3];
+    float zprobe_zoffset;
+    float Kp;
+    float Ki;
+    float Kd;
+    float bedKp;
+    float bedKi;
+    float bedKd;
+    int lcd_contrast;
+    bool autoretract_enabled;
+    float retract_length;
+    float retract_feedrate;
+    float retract_zlift;
+    float retract_recover_length;
+    float retract_recover_feedrate;
+    bool volumetric_enabled;
+    float filament_size;
+    float max_feedrate_silent[4];
+    unsigned long max_acceleration_units_per_sq_second_silent[4];
+} __attribute__ ((packed)) M500_conf;
 bool Config_RetrieveSettings(uint16_t offset)
 {
     int i=offset;