Cleaned-up limit pin reporting and comments.

- Cleaned up the limit pin state reporting option to display only the
state per axis, rather than the whole port. It’s organized by an XYZ
order, 0(low)-1(high), and generally looks like `Lim:001`.

- Separated the control pin state reporting from limit state reporting
as a new compile option. This stayed the same in terms of showing the
entire port in binary, since it’s not anticipated that this will be
used much, if at all.

- Updated some of the gcode source comments regarding supported g-codes.

grbl/config.h

@@ -156,11 +156,18 @@
 // NOTE: Will eventually be added to Grbl settings in v1.0.
 // #define INVERT_CONTROL_PIN // Default disabled. Uncomment to enable.
 
-// Enable input pin states feedback in status reports. The data is presented as a binary value with
+// Enable limit pin states feedback in status reports. The data is presented as 0 (low) or 1(high), 
-// the bits in the appropriate input pin ports being 0(low) or 1(high). Useful for setting up a new
+// where the order is XYZ. For example, if the Y- and Z-limit pins are active, Grbl will include the 
-// CNC machine, but do not recommend keeping this option by default, as it will consume CPU resources
+// following string in the status report "Lim:011". This is generally useful for setting up a new
-// with little to no benefit during normal operation.
+// CNC machine, but we do not recommend keeping this option enabled, as it will consume CPU resources
-// #define REPORT_INPUT_PIN_STATES // Default disabled. Uncomment to enable.
+// with little to no benefit during normal operation and it may not be supported by most GUIs.
+// #define REPORT_LIMIT_PIN_STATE // Default disabled. Uncomment to enable.
+
+// Enable control pin states feedback in status reports. The data is presented as simple binary of
+// the control pin port (0 (low) or 1(high)), masked to show only the input pins. Non-control pins on the 
+// port will always show a 0 value. See cpu_map.h for the pin bitmap. As with the limit pin reporting,
+// we do not recommend keeping this option enabled. Try to only use this for setting up a new CNC.
+// #define REPORT_CONTROL_PIN_STATE // Default disabled. Uncomment to enable.
 
 // When Grbl powers-cycles or is hard reset with the Arduino reset button, Grbl boots up with no ALARM
 // by default. This is to make it as simple as possible for new users to start using Grbl. When homing

grbl/gcode.c

@@ -1056,9 +1056,9 @@ uint8_t gc_execute_line(char *line)
    group 1 = {G81 - G89} (Motion modes: Canned cycles)
    group 4 = {M1} (Optional stop, ignored)
    group 6 = {M6} (Tool change)
-   group 7 = {G40, G41, G42} cutter radius compensation
+   group 7 = {G41, G42} cutter radius compensation (G40 is supported)
-   group 8 = {G43} tool length offset (But G43.1/G94 IS SUPPORTED)
+   group 8 = {G43} tool length offset (G43.1/G49 are supported)
-   group 8 = {*M7} enable mist coolant
+   group 8 = {*M7} enable mist coolant (* Compile-option)
    group 9 = {M48, M49} enable/disable feed and speed override switches
    group 10 = {G98, G99} return mode canned cycles
    group 13 = {G61, G61.1, G64} path control mode

grbl/gcode.h

@@ -30,14 +30,14 @@
 // and are similar/identical to other g-code interpreters by manufacturers (Haas,Fanuc,Mazak,etc).
 // NOTE: Modal group define values must be sequential and starting from zero.
 #define MODAL_GROUP_G0 0 // [G4,G10,G28,G28.1,G30,G30.1,G53,G92,G92.1] Non-modal
-#define MODAL_GROUP_G1 1 // [G0,G1,G2,G3,G38.2,G80] Motion
+#define MODAL_GROUP_G1 1 // [G0,G1,G2,G3,G38.2,G38.3,G38.4,G38.5,G80] Motion
 #define MODAL_GROUP_G2 2 // [G17,G18,G19] Plane selection
 #define MODAL_GROUP_G3 3 // [G90,G91] Distance mode
-#define MODAL_GROUP_G4 4 // [G90.1,G91.1] Arc IJK distance mode
+#define MODAL_GROUP_G4 4 // [G91.1] Arc IJK distance mode
 #define MODAL_GROUP_G5 5 // [G93,G94] Feed rate mode
 #define MODAL_GROUP_G6 6 // [G20,G21] Units
 #define MODAL_GROUP_G7 7 // [G40] Cutter radius compensation mode. G41/42 NOT SUPPORTED.
-#define MODAL_GROUP_G8 8 // [G43,G43.1,G49] Tool length offset
+#define MODAL_GROUP_G8 8 // [G43.1,G49] Tool length offset
 #define MODAL_GROUP_G12 9 // [G54,G55,G56,G57,G58,G59] Coordinate system selection
 
 #define MODAL_GROUP_M4 10  // [M0,M1,M2,M30] Stopping
@@ -142,8 +142,9 @@ typedef struct {
   uint8_t feed_rate;       // {G93,G94}
   uint8_t units;           // {G20,G21}
   uint8_t distance;        // {G90,G91}
+  // uint8_t distance_arc; // {G91.1} NOTE: Don't track. Only one supported.
   uint8_t plane_select;    // {G17,G18,G19}
-  // uint8_t cutter_comp;  // {G40} NOTE: Don't need to track since it's always disabled.
+  // uint8_t cutter_comp;  // {G40} NOTE: Don't track. Only one supported.
   uint8_t tool_length;     // {G43.1,G49}
   uint8_t coord_select;    // {G54,G55,G56,G57,G58,G59}
   uint8_t program_flow;    // {M0,M1,M2,M30}

grbl/grbl.h

@@ -23,7 +23,7 @@
 
 // Grbl versioning system
 #define GRBL_VERSION "0.9i"
-#define GRBL_VERSION_BUILD "20150307"
+#define GRBL_VERSION_BUILD "20150314"
 
 // Define standard libraries used by Grbl.
 #include <avr/io.h>

grbl/report.c

@@ -484,9 +484,16 @@ void report_realtime_status()
     printFloat_RateValue(st_get_realtime_rate());
   #endif    
   
-  #ifdef REPORT_INPUT_PIN_STATES
+  #ifdef REPORT_LIMIT_PIN_STATE
     printPgmString(PSTR(",Lim:"));
-    print_uint8_base2(LIMIT_PIN & LIMIT_MASK);  
+    uint8_t idx;
+    for (idx=0; idx<N_AXIS; idx++) {
+      if (LIMIT_PIN & get_limit_pin_mask(idx)) { printString(PSTR("1")); }
+      else { printString(PSTR("0")); }
+    }
+  #endif
+  
+  #ifdef REPORT_CONTROL_PIN_STATE 
     printPgmString(PSTR(",Ctl:"));
     print_uint8_base2(CONTROL_PIN & CONTROL_MASK);
   #endif