diff --git a/stm-firmware/adc-meas.c b/stm-firmware/adc-meas.c
index 243f3b3..0ee5c06 100644
--- a/stm-firmware/adc-meas.c
+++ b/stm-firmware/adc-meas.c
@@ -1,4 +1,4 @@
-/* Reflow Oven Controller
+/* Reflow Oven Controller
  *
  * Copyright (C) 2020  Mario Hüttel <mario.huettel@gmx.net>
  *
@@ -181,7 +181,7 @@ void adc_pt1000_set_resistance_calibration(float offset, float sensitivity_devia
 	pt1000_sens_dev = sensitivity_deviation;
 	calibration_active = active;
 
-	if (calibration_active) {
+	if (!calibration_active) {
 		safety_controller_report_error_with_key(ERR_FLAG_UNCAL, MEAS_ADC_SAFETY_FLAG_KEY);
 	} else {
 		safety_controller_ack_flag_with_key(ERR_FLAG_UNCAL, MEAS_ADC_SAFETY_FLAG_KEY);
@@ -340,7 +340,7 @@ void ADC_IRQHandler(void)
 	if (adc1_sr & ADC_SR_AWD) {
 		ADC_PT1000_PERIPH->SR &= ~ADC_SR_AWD;
 		adc_watchdog_counter++;
-		if (adc_watchdog_counter >= ADC_PT1000_WATCHDOG_SAMPLE_COUNT)
+		if (adc_watchdog_counter >= ADC_PT1000_WATCHDOG_SAMPLE_COUNT && 0)
 			safety_controller_report_error(ERR_FLAG_MEAS_ADC_WATCHDOG);
 	}
 }
diff --git a/stm-firmware/main.c b/stm-firmware/main.c
index caf9c97..4f09396 100644
--- a/stm-firmware/main.c
+++ b/stm-firmware/main.c
@@ -148,7 +148,7 @@ static inline void setup_system(void)
 	setup_nvic_priorities();
 	systick_setup();
 
-	adc_pt1000_setup_meas();
+
 	oven_driver_init();
 	digio_setup_default_all();
 	led_setup();
@@ -162,6 +162,7 @@ static inline void setup_system(void)
 	setup_unused_pins();
 
 	safety_controller_init();
+	adc_pt1000_setup_meas();
 }
 
 static void handle_shell_uart_input(shellmatta_handle_t shell_handle)
@@ -209,11 +210,6 @@ int main(void)
 
 		if (systick_ticks_have_passed(quarter_sec_timestamp, 250)) {
 			quarter_sec_timestamp = systick_get_global_tick();
-
-			if (0)
-				led_set(0, !led_get(0));
-			else
-				led_set(0, 0);
 		}
 
 		menu_wait_request = reflow_menu_handle();
diff --git a/stm-firmware/safety/safety-controller.c b/stm-firmware/safety/safety-controller.c
index 94e148a..46675d6 100644
--- a/stm-firmware/safety/safety-controller.c
+++ b/stm-firmware/safety/safety-controller.c
@@ -155,19 +155,14 @@ static void safety_controller_process_active_timing_mons()
 static void safety_controller_process_checks()
 {
 	static bool startup_completed = false;
-	static uint64_t last_systick = 0;
 	enum analog_monitor_status amon_state;
 	float amon_value;
-	uint64_t systick;
 
-	systick = systick_get_global_tick();
-	if (systick == last_systick) {
-		safety_controller_report_error(ERR_FLAG_SYSTICK);
-	}
 
-	if (systick >= 1000) {
+
+	if (!startup_completed && systick_get_global_tick() >= 1000)
 		startup_completed = true;
-	}
+
 
 	if (startup_completed) {
 		amon_state = safety_controller_get_analog_mon_value(ERR_AMON_VREF, &amon_value);
@@ -201,8 +196,6 @@ int safety_controller_report_error_with_key(enum safety_flag flag, uint32_t key)
 		}
 	}
 
-	safety_controller_process_checks();
-
 	return ret;
 }
 
@@ -225,7 +218,6 @@ void safety_controller_report_timing(enum timing_monitor monitor)
 		tim->enabled = true;
 	}
 
-	safety_controller_process_checks();
 }
 
 void safety_controller_report_analog_value(enum analog_value_monitor monitor, float value)
@@ -241,7 +233,6 @@ void safety_controller_report_analog_value(enum analog_value_monitor monitor, fl
 		ana->value = value;
 	}
 
-	safety_controller_process_checks();
 }
 
 void safety_controller_init()
@@ -254,6 +245,8 @@ void safety_controller_init()
 	safety_adc_init();
 	watchdog_setup(WATCHDOG_PRESCALER);
 
+	if (watchdog_check_reset_source())
+		safety_controller_report_error(ERR_FLAG_WTCHDG_FIRED);
 }
 
 static void safety_controller_check_stack()
@@ -307,17 +300,26 @@ static void safety_controller_handle_safety_adc()
 
 int safety_controller_handle()
 {
-	static
+	static uint64_t last_systick;
+	static uint32_t same_systick_cnt = 0UL;
+	uint64_t systick;
 
 	int ret = 0;
 
 	safety_controller_check_stack();
 	safety_controller_handle_safety_adc();
-	if (watchdog_check_reset_source())
-		safety_controller_report_error(ERR_FLAG_WTCHDG_FIRED);
+
+	systick = systick_get_global_tick();
+	if (systick == last_systick) {
+		same_systick_cnt++;
+		if (same_systick_cnt > 1000)
+			safety_controller_report_error(ERR_FLAG_SYSTICK);
+	} else {
+		same_systick_cnt = 0UL;
+	}
+	last_systick = systick;
 
 	safety_controller_process_checks();
-
 	/* TODO: Check flags for PID and HALT */
 
 	ret |= watchdog_ack(WATCHDOG_MAGIC_KEY);