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diff --git a/Marlin/src/feature/probe_temp_comp.cpp b/Marlin/src/feature/probe_temp_comp.cpp
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+++ b/Marlin/src/feature/probe_temp_comp.cpp
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+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "../inc/MarlinConfigPre.h"
+
+#if ENABLED(PROBE_TEMP_COMPENSATION)
+
+#include "probe_temp_comp.h"
+#include <math.h>
+
+ProbeTempComp temp_comp;
+
+int16_t ProbeTempComp::z_offsets_probe[cali_info_init[TSI_PROBE].measurements],  // = {0}
+        ProbeTempComp::z_offsets_bed[cali_info_init[TSI_BED].measurements];      // = {0}
+
+#if ENABLED(USE_TEMP_EXT_COMPENSATION)
+  int16_t ProbeTempComp::z_offsets_ext[cali_info_init[TSI_EXT].measurements];    // = {0}
+#endif
+
+int16_t *ProbeTempComp::sensor_z_offsets[TSI_COUNT] = {
+  ProbeTempComp::z_offsets_probe, ProbeTempComp::z_offsets_bed
+  #if ENABLED(USE_TEMP_EXT_COMPENSATION)
+    , ProbeTempComp::z_offsets_ext
+  #endif
+};
+
+const temp_calib_t ProbeTempComp::cali_info[TSI_COUNT] = {
+  cali_info_init[TSI_PROBE], cali_info_init[TSI_BED]
+  #if ENABLED(USE_TEMP_EXT_COMPENSATION)
+    , cali_info_init[TSI_EXT]
+  #endif
+};
+
+constexpr xyz_pos_t ProbeTempComp::park_point;
+constexpr xy_pos_t ProbeTempComp::measure_point;
+constexpr int ProbeTempComp::probe_calib_bed_temp;
+
+uint8_t ProbeTempComp::calib_idx; // = 0
+float ProbeTempComp::init_measurement; // = 0.0
+
+void ProbeTempComp::clear_offsets(const TempSensorID tsi) {
+  LOOP_L_N(i, cali_info[tsi].measurements)
+    sensor_z_offsets[tsi][i] = 0;
+  calib_idx = 0;
+}
+
+bool ProbeTempComp::set_offset(const TempSensorID tsi, const uint8_t idx, const int16_t offset) {
+  if (idx >= cali_info[tsi].measurements) return false;
+  sensor_z_offsets[tsi][idx] = offset;
+  return true;
+}
+
+void ProbeTempComp::print_offsets() {
+  LOOP_L_N(s, TSI_COUNT) {
+    float temp = cali_info[s].start_temp;
+    for (int16_t i = -1; i < cali_info[s].measurements; ++i) {
+      serialprintPGM(s == TSI_BED ? PSTR("Bed") :
+        #if ENABLED(USE_TEMP_EXT_COMPENSATION)
+          s == TSI_EXT ? PSTR("Extruder") :
+        #endif
+        PSTR("Probe")
+      );
+      SERIAL_ECHOLNPAIR(
+        " temp: ", temp,
+        "C; Offset: ", i < 0 ? 0.0f : sensor_z_offsets[s][i], " um"
+      );
+      temp += cali_info[s].temp_res;
+    }
+  }
+}
+
+void ProbeTempComp::prepare_new_calibration(const float &init_meas_z) {
+  calib_idx = 0;
+  init_measurement = init_meas_z;
+}
+
+void ProbeTempComp::push_back_new_measurement(const TempSensorID tsi, const float &meas_z) {
+  switch (tsi) {
+    case TSI_PROBE:
+    case TSI_BED:
+    //case TSI_EXT:
+      if (calib_idx >= cali_info[tsi].measurements) return;
+      sensor_z_offsets[tsi][calib_idx++] = static_cast<int16_t>(meas_z * 1000.0f - init_measurement * 1000.0f);
+    default: break;
+  }
+}
+
+bool ProbeTempComp::finish_calibration(const TempSensorID tsi) {
+  if (tsi != TSI_PROBE && tsi != TSI_BED) return false;
+
+  if (calib_idx < 3) {
+    SERIAL_ECHOLNPGM("!Insufficient measurements (min. 3).");
+    clear_offsets(tsi);
+    return false;
+  }
+
+  const uint8_t measurements = cali_info[tsi].measurements;
+  const float start_temp = cali_info[tsi].start_temp,
+                res_temp = cali_info[tsi].temp_res;
+  int16_t * const data = sensor_z_offsets[tsi];
+
+  // Extrapolate
+  float k, d;
+  if (calib_idx < measurements) {
+    SERIAL_ECHOLNPAIR("Got ", calib_idx, " measurements. ");
+    if (linear_regression(tsi, k, d)) {
+      SERIAL_ECHOPGM("Applying linear extrapolation");
+      calib_idx--;
+      for (; calib_idx < measurements; ++calib_idx) {
+        const float temp = start_temp + float(calib_idx) * res_temp;
+        data[calib_idx] = static_cast<int16_t>(k * temp + d);
+      }
+    }
+    else {
+      // Simply use the last measured value for higher temperatures
+      SERIAL_ECHOPGM("Failed to extrapolate");
+      const int16_t last_val = data[calib_idx];
+      for (; calib_idx < measurements; ++calib_idx)
+        data[calib_idx] = last_val;
+    }
+    SERIAL_ECHOLNPGM(" for higher temperatures.");
+  }
+
+  // Sanity check
+  for (calib_idx = 0; calib_idx < measurements; ++calib_idx) {
+    // Restrict the max. offset
+    if (abs(data[calib_idx]) > 2000) {
+      SERIAL_ECHOLNPGM("!Invalid Z-offset detected (0-2).");
+      clear_offsets(tsi);
+      return false;
+    }
+    // Restrict the max. offset difference between two probings
+    if (calib_idx > 0 && abs(data[calib_idx - 1] - data[calib_idx]) > 800) {
+      SERIAL_ECHOLNPGM("!Invalid Z-offset between two probings detected (0-0.8).");
+      clear_offsets(TSI_PROBE);
+      return false;
+    }
+  }
+
+  return true;
+}
+
+void ProbeTempComp::compensate_measurement(const TempSensorID tsi, const float &temp, float &meas_z) {
+  if (WITHIN(temp, cali_info[tsi].start_temp, cali_info[tsi].end_temp))
+    meas_z -= get_offset_for_temperature(tsi, temp);
+}
+
+float ProbeTempComp::get_offset_for_temperature(const TempSensorID tsi, const float &temp) {
+  const uint8_t measurements = cali_info[tsi].measurements;
+  const float start_temp = cali_info[tsi].start_temp,
+                res_temp = cali_info[tsi].temp_res;
+  const int16_t * const data = sensor_z_offsets[tsi];
+
+  auto point = [&](uint8_t i) {
+    return xy_float_t({start_temp + i*res_temp, static_cast<float>(data[i])});
+  };
+
+  auto linear_interp = [](float x, xy_float_t p1, xy_float_t p2) {
+    return (p2.y - p1.y) / (p2.x - p2.y) * (x - p1.x) + p1.y;
+  };
+
+  // Linear interpolation
+  uint8_t idx = static_cast<uint8_t>((temp - start_temp) / res_temp);
+
+  // offset in um
+  float offset = 0.0f;
+
+  #if !defined(PTC_LINEAR_EXTRAPOLATION) || PTC_LINEAR_EXTRAPOLATION <= 0
+    if (idx < 0)
+      offset = 0.0f;
+    else if (idx > measurements - 2)
+      offset = static_cast<float>(data[measurements - 1]);
+  #else
+    if (idx < 0)
+      offset = linear_interp(temp, point(0), point(PTC_LINEAR_EXTRAPOLATION));
+    else if (idx > measurements - 2)
+      offset = linear_interp(temp, point(measurements - PTC_LINEAR_EXTRAPOLATION - 1), point(measurements - 1));
+  #endif
+    else
+      offset = linear_interp(temp, point(idx), point(idx + 1));
+
+  // return offset in mm
+  return offset / 1000.0f;
+}
+
+bool ProbeTempComp::linear_regression(const TempSensorID tsi, float &k, float &d) {
+  if (tsi != TSI_PROBE && tsi != TSI_BED) return false;
+
+  if (!WITHIN(calib_idx, 2, cali_info[tsi].measurements)) return false;
+
+  const float start_temp = cali_info[tsi].start_temp,
+                res_temp = cali_info[tsi].temp_res;
+  const int16_t * const data = sensor_z_offsets[tsi];
+
+  float sum_x = start_temp,
+        sum_x2 = sq(start_temp),
+        sum_xy = 0, sum_y = 0;
+
+  LOOP_L_N(i, calib_idx) {
+    const float xi = start_temp + (i + 1) * res_temp,
+                yi = static_cast<float>(data[i]);
+    sum_x += xi;
+    sum_x2 += sq(xi);
+    sum_xy += xi * yi;
+    sum_y += yi;
+  }
+
+  const float denom = static_cast<float>(calib_idx + 1) * sum_x2 - sq(sum_x);
+  if (fabs(denom) <= 10e-5) {
+    // Singularity - unable to solve
+    k = d = 0.0;
+    return false;
+  }
+
+  k = (static_cast<float>(calib_idx + 1) * sum_xy - sum_x * sum_y) / denom;
+  d = (sum_y - k * sum_x) / static_cast<float>(calib_idx + 1);
+
+  return true;
+}
+
+#endif // PROBE_TEMP_COMPENSATION