Probe cleanup (#625)

* Cleanup probing code

* Update Grbl.h

* Update after review

Grbl_Esp32/src/Defaults.h

@@ -599,6 +599,10 @@
 #    define USER_ANALOG_PIN_3 UNDEFINED_PIN
 #endif
 
+#ifndef PROBE_PIN
+#    define PROBE_PIN UNDEFINED_PIN
+#endif
+
 #ifndef USER_ANALOG_PIN_0_FREQ
 #    define USER_ANALOG_PIN_0_FREQ 5000
 #endif

Grbl_Esp32/src/GCode.cpp

@@ -271,10 +271,11 @@ Error gc_execute_line(char* line, uint8_t client) {
                         mg_word_bit           = ModalGroup::MG1;
                         break;
                     case 38:  // G38 - probe
-#ifndef PROBE_PIN             //only allow G38 "Probe" commands if a probe pin is defined.
+                        //only allow G38 "Probe" commands if a probe pin is defined.
+                        if (PROBE_PIN == UNDEFINED_PIN) {
                             grbl_msg_sendf(CLIENT_SERIAL, MsgLevel::Info, "No probe pin defined");
                             FAIL(Error::GcodeUnsupportedCommand);  // [Unsupported G command]
-#endif
+                        }
                         // Check for G0/1/2/3/38 being called with G10/28/30/92 on same block.
                         // * G43.1 is also an axis command but is not explicitly defined this way.
                         if (axis_command != AxisCommand::None) {

Grbl_Esp32/src/Grbl.h

@@ -23,7 +23,7 @@
 // Grbl versioning system
 
 const char* const GRBL_VERSION       = "1.3a";
-const char* const GRBL_VERSION_BUILD = "20201001";
+const char* const GRBL_VERSION_BUILD = "20201004";
 
 //#include <sdkconfig.h>
 #include <Arduino.h>

Grbl_Esp32/src/MotionControl.cpp

@@ -375,13 +375,12 @@ GCUpdatePos mc_probe_cycle(float* target, plan_line_data_t* pl_data, uint8_t par
     uint8_t is_probe_away = bit_istrue(parser_flags, GCParserProbeIsAway);
     uint8_t is_no_error   = bit_istrue(parser_flags, GCParserProbeIsNoError);
     sys.probe_succeeded   = false;  // Re-initialize probe history before beginning cycle.
-    probe_configure_invert_mask(is_probe_away);
+    set_probe_direction(is_probe_away);
     // After syncing, check if probe is already triggered. If so, halt and issue alarm.
     // NOTE: This probe initialization error applies to all probing cycles.
-    if (probe_get_state()) {  // Check probe pin state.
+    if (probe_get_state() ^ is_probe_away) {  // Check probe pin state.
         system_set_exec_alarm(ExecAlarm::ProbeFailInitial);
         protocol_execute_realtime();
-        probe_configure_invert_mask(false);  // Re-initialize invert mask before returning.
         return GCUpdatePos::None;  // Nothing else to do but bail.
     }
     // Setup and queue probing motion. Auto cycle-start should not start the cycle.
@@ -408,7 +407,6 @@ GCUpdatePos mc_probe_cycle(float* target, plan_line_data_t* pl_data, uint8_t par
         sys.probe_succeeded = true;  // Indicate to system the probing cycle completed successfully.
     }
     sys_probe_state = PROBE_OFF;  // Ensure probe state monitor is disabled.
-    probe_configure_invert_mask(false);  // Re-initialize invert mask.
     protocol_execute_realtime();  // Check and execute run-time commands
     // Reset the stepper and planner buffers to remove the remainder of the probe motion.
     st_reset();            // Reset step segment buffer.

Grbl_Esp32/src/Probe.cpp

@@ -24,47 +24,40 @@
 #include "Grbl.h"
 
 // Inverts the probe pin state depending on user settings and probing cycle mode.
-uint8_t probe_invert_mask;
+static bool is_probe_away;
 
 // Probe pin initialization routine.
 void probe_init() {
-#ifdef PROBE_PIN
+    static bool show_init_msg = true;  // used to show message only once.
-#    ifdef DISABLE_PROBE_PIN_PULL_UP
+
+    if (PROBE_PIN != UNDEFINED_PIN) {
+#ifdef DISABLE_PROBE_PIN_PULL_UP
         pinMode(PROBE_PIN, INPUT);
-#    else
+#else
         pinMode(PROBE_PIN, INPUT_PULLUP);  // Enable internal pull-up resistors. Normal high operation.
-#    endif
-    probe_configure_invert_mask(false);  // Initialize invert mask.
 #endif
+
+        if (show_init_msg) {
+            grbl_msg_sendf(CLIENT_SERIAL, MsgLevel::Info, "Probe on pin %s", pinName(PROBE_PIN).c_str());
+            show_init_msg = false;
+        }
+    }
 }
 
-// Called by probe_init() and the mc_probe() routines. Sets up the probe pin invert mask to
+void set_probe_direction(bool is_away) {
-// appropriately set the pin logic according to setting for normal-high/normal-low operation
+    is_probe_away = is_away;
-// and the probing cycle modes for toward-workpiece/away-from-workpiece.
-void probe_configure_invert_mask(uint8_t is_probe_away) {
-    probe_invert_mask = 0;  // Initialize as zero.
-    if (probe_invert->get()) {
-        probe_invert_mask ^= PROBE_MASK;
-    }
-    if (is_probe_away) {
-        probe_invert_mask ^= PROBE_MASK;
-    }
 }
 
 // Returns the probe pin state. Triggered = true. Called by gcode parser and probe state monitor.
-uint8_t probe_get_state() {
+bool probe_get_state() {
-#ifdef PROBE_PIN
+    return digitalRead(PROBE_PIN) ^ probe_invert->get();
-    return digitalRead(PROBE_PIN) ^ probe_invert_mask;
-#else
-    return false;
-#endif
 }
 
 // Monitors probe pin state and records the system position when detected. Called by the
 // stepper ISR per ISR tick.
 // NOTE: This function must be extremely efficient as to not bog down the stepper ISR.
 void probe_state_monitor() {
-    if (probe_get_state()) {
+    if (probe_get_state() ^ is_probe_away) {
         sys_probe_state = PROBE_OFF;
         memcpy(sys_probe_position, sys_position, sizeof(sys_position));
         bit_true(sys_rt_exec_state, EXEC_MOTION_CANCEL);

Grbl_Esp32/src/Probe.h

@@ -30,13 +30,11 @@ const int PROBE_ACTIVE = 1;  // Actively watching the input pin.
 // Probe pin initialization routine.
 void probe_init();
 
-// Called by probe_init() and the mc_probe() routines. Sets up the probe pin invert mask to
+// setup probing direction G38.2 vs. G38.4
-// appropriately set the pin logic according to setting for normal-high/normal-low operation
+void set_probe_direction(bool is_away);
-// and the probing cycle modes for toward-workpiece/away-from-workpiece.
-void probe_configure_invert_mask(uint8_t is_probe_away);
 
 // Returns probe pin state. Triggered = true. Called by gcode parser and probe state monitor.
-uint8_t probe_get_state();
+bool probe_get_state();
 
 // Monitors probe pin state and records the system position when detected. Called by the
 // stepper ISR per ISR tick.

Grbl_Esp32/src/Settings.cpp

@@ -537,6 +537,10 @@ void FlagSetting::setDefault() {
 
 Error FlagSetting::setStringValue(char* s) {
     s             = trim(s);
+    Error err = check(s);
+    if (err != Error::Ok) {
+        return err;
+    }
     _currentValue = (strcasecmp(s, "on") == 0) || (strcasecmp(s, "true") == 0) || (strcasecmp(s, "enabled") == 0) ||
                     (strcasecmp(s, "yes") == 0) || (strcasecmp(s, "1") == 0);
     // _storedValue is -1, 0, or 1