From aa0f7afbe67e95541134878b9520aec329492cc0 Mon Sep 17 00:00:00 2001
From: InsanityAutomation
 <38436470+InsanityAutomation@users.noreply.github.com>
Date: Mon, 15 Apr 2019 16:57:34 -0400
Subject: [PATCH] Fix call to uninitialized PWM pin, heater 2 overlap (#13674)

---
 Marlin/src/gcode/control/M3-M5.cpp   | 4 +++-
 Marlin/src/pins/pins_FORMBOT_TREX3.h | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/Marlin/src/gcode/control/M3-M5.cpp b/Marlin/src/gcode/control/M3-M5.cpp
index 8612e0c03f..132f7bb399 100644
--- a/Marlin/src/gcode/control/M3-M5.cpp
+++ b/Marlin/src/gcode/control/M3-M5.cpp
@@ -74,7 +74,9 @@ inline void delay_for_power_down() { safe_delay(SPINDLE_LASER_POWERDOWN_DELAY);
 
 inline void set_spindle_laser_ocr(const uint8_t ocr) {
   WRITE(SPINDLE_LASER_ENA_PIN, SPINDLE_LASER_ENABLE_INVERT); // turn spindle on (active low)
-  analogWrite(SPINDLE_LASER_PWM_PIN, (SPINDLE_LASER_PWM_INVERT) ? 255 - ocr : ocr);
+  #if ENABLED(SPINDLE_LASER_PWM)
+    analogWrite(SPINDLE_LASER_PWM_PIN, (SPINDLE_LASER_PWM_INVERT) ? 255 - ocr : ocr);
+  #endif
 }
 
 #if ENABLED(SPINDLE_LASER_PWM)
diff --git a/Marlin/src/pins/pins_FORMBOT_TREX3.h b/Marlin/src/pins/pins_FORMBOT_TREX3.h
index 3615ca742c..5b4bd8b533 100644
--- a/Marlin/src/pins/pins_FORMBOT_TREX3.h
+++ b/Marlin/src/pins/pins_FORMBOT_TREX3.h
@@ -143,7 +143,7 @@
   #define LED_PIN          13
 #endif
 
-#define SPINDLE_LASER_PWM_PIN     7   // MUST BE HARDWARE PWM
+#define SPINDLE_LASER_PWM_PIN    -1   // MUST BE HARDWARE PWM
 #define SPINDLE_LASER_ENA_PIN     4   // Pin should have a pullup!
 
 // Use the RAMPS 1.4 Analog input 5 on the AUX2 connector