From 892e83e8723ecd395b334c554fd13faa32534e04 Mon Sep 17 00:00:00 2001
From: Scott Lahteine <thinkyhead@users.noreply.github.com>
Date: Sun, 27 Dec 2020 16:23:18 -0600
Subject: [PATCH] Init tare pin once

---
 Marlin/src/MarlinCore.cpp   |  6 +++++-
 Marlin/src/module/probe.cpp | 14 ++++++++++++--
 Marlin/src/module/probe.h   |  1 +
 3 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/Marlin/src/MarlinCore.cpp b/Marlin/src/MarlinCore.cpp
index 0171690d4..9a3de3f1a 100644
--- a/Marlin/src/MarlinCore.cpp
+++ b/Marlin/src/MarlinCore.cpp
@@ -193,7 +193,7 @@
   #include "feature/runout.h"
 #endif
 
-#if HAS_Z_SERVO_PROBE
+#if EITHER(PROBE_TARE, HAS_Z_SERVO_PROBE)
   #include "module/probe.h"
 #endif
 
@@ -1119,6 +1119,10 @@ void setup() {
     SETUP_RUN(ui.reset_status());     // Load welcome message early. (Retained if no errors exist.)
   #endif
 
+  #if ENABLED(PROBE_TARE)
+    SETUP_RUN(probe.tare_init());
+  #endif
+
   #if BOTH(SDSUPPORT, SDCARD_EEPROM_EMULATION)
     SETUP_RUN(card.mount());          // Mount media with settings before first_load
   #endif
diff --git a/Marlin/src/module/probe.cpp b/Marlin/src/module/probe.cpp
index df014bdc2..53c35d69f 100644
--- a/Marlin/src/module/probe.cpp
+++ b/Marlin/src/module/probe.cpp
@@ -510,6 +510,16 @@ bool Probe::probe_down_to_z(const float z, const feedRate_t fr_mm_s) {
 }
 
 #if ENABLED(PROBE_TARE)
+
+  /**
+   * @brief Init the tare pin
+   *
+   * @details Init tare pin to ON state for a strain gauge, otherwise OFF
+   */
+  void Probe::tare_init() {
+    OUT_WRITE(PROBE_TARE_PIN, !PROBE_TARE_STATE);
+  }
+
   /**
    * @brief Tare the Z probe
    *
@@ -526,9 +536,9 @@ bool Probe::probe_down_to_z(const float z, const feedRate_t fr_mm_s) {
     #endif
 
     SERIAL_ECHOLNPGM("Taring probe");
-    OUT_WRITE(PROBE_TARE_PIN, PROBE_TARE_STATE);
+    WRITE(PROBE_TARE_PIN, PROBE_TARE_STATE);
     delay(PROBE_TARE_TIME);
-    OUT_WRITE(PROBE_TARE_PIN, !PROBE_TARE_STATE);
+    WRITE(PROBE_TARE_PIN, !PROBE_TARE_STATE);
     delay(PROBE_TARE_DELAY);
 
     endstops.hit_on_purpose();
diff --git a/Marlin/src/module/probe.h b/Marlin/src/module/probe.h
index 49520eb33..527f1190f 100644
--- a/Marlin/src/module/probe.h
+++ b/Marlin/src/module/probe.h
@@ -211,6 +211,7 @@ public:
   #endif
 
   #if ENABLED(PROBE_TARE)
+    static void tare_init();
     static bool tare();
   #endif