diff --git a/lib/obus_module.cpp b/lib/obus_module.cpp
index fb1351b..74b9429 100644
--- a/lib/obus_module.cpp
+++ b/lib/obus_module.cpp
@@ -8,6 +8,8 @@
 #define BLINK_DELAY_NORMAL 500
 #define BLINK_DELAY_FAST 300
 
+#define MAX_TIME_BETWEEN_CALLS 100
+
 // Not used normally
 #define MCP_INT 2
 
@@ -21,6 +23,7 @@ namespace obus_module {
 struct obus_can::module this_module;
 uint8_t strike_count;
 bool active;
+uint32_t next_loop_call_deadline;
 
 // Current LED status
 struct color { bool red; bool green; };
@@ -81,6 +84,7 @@ void _setLedBlink(struct color color, uint16_t delay) {
 void _resetState() {
 	strike_count = 0;
 	active = false;
+	next_loop_call_deadline = 0;
 
 	if (this_module.type == OBUS_TYPE_PUZZLE || this_module.type == OBUS_TYPE_NEEDY) {
 		pinMode(RED_LED, OUTPUT);
@@ -113,21 +117,31 @@ void empty_callback_state(uint32_t time_left, uint8_t strikes, uint8_t max_strik
 	(void)puzzle_modules_solved;
 }
 
+void blink_error(String message) {
+	bool blink = false;
+	while (true) {
+		digitalWrite(RED_LED, blink);
+		digitalWrite(GREEN_LED, blink);
+		blink = !blink;
+		delay(BLINK_DELAY_NORMAL);
+		Serial.println(message);
+	}
+}
+
 bool loopPuzzle(obus_can::message* message, void (*callback_game_start)(), void (*callback_game_stop)(), void (*callback_info)(uint8_t info_id, uint8_t infomessage[7]), void (*callback_state)(uint32_t time_left, uint8_t strikes, uint8_t max_strikes, uint8_t puzzle_modules_solved)) {
 	// TODO this can be more efficient by only enabling error interrupts and
 	//  reacting to the interrupt instead of checking if the flag is set in a loop
 	// We will need to fork our CAN library for this, because the needed functions are private.
 	// Also, we can't do this by default, because the INT pin is normally not connected to the board
 	if (obus_can::is_error_condition()) {
-		bool blink = false;
-		while (true) {
-			digitalWrite(RED_LED, blink);
-			digitalWrite(GREEN_LED, blink);
-			blink = !blink;
-			delay(BLINK_DELAY_NORMAL);
-		}
+		blink_error(F("E CAN error"));
 	}
 
+	if (next_loop_call_deadline != 0 && millis() > next_loop_call_deadline) {
+		blink_error(F("E missed deadline"));
+	}
+	next_loop_call_deadline = millis() + MAX_TIME_BETWEEN_CALLS;
+
 	bool received_message = false;
 	if (obus_can::receive(message)) {
 		received_message = true;
diff --git a/misc/reverse_engineered_hardware/month_day_selector/month_day_selector.ino b/misc/reverse_engineered_hardware/month_day_selector/month_day_selector.ino
index eef29eb..976e01f 100644
--- a/misc/reverse_engineered_hardware/month_day_selector/month_day_selector.ino
+++ b/misc/reverse_engineered_hardware/month_day_selector/month_day_selector.ino
@@ -18,7 +18,7 @@ uint8_t shiftInFixed(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder) {
 	 else
 	 	value |= digitalRead(dataPin) << (7 - i);
 	 digitalWrite(clockPin, HIGH);
-	 delay(1);
+	 delayMicroseconds(3);
 	 digitalWrite(clockPin, LOW);
  }
  return value;
@@ -50,7 +50,7 @@ void loop() // run over and over
 {
 	// read data in
 	digitalWrite(READ_PIN, HIGH);
-	delay(200);
+	delayMicroseconds(3);
 	digitalWrite(READ_PIN, LOW);
 
 	// shift data bit by bit
diff --git a/src/modules/puzzle_testmodule_date/puzzle_testmodule_date.ino b/src/modules/puzzle_testmodule_date/puzzle_testmodule_date.ino
index 3509a11..c0a5890 100644
--- a/src/modules/puzzle_testmodule_date/puzzle_testmodule_date.ino
+++ b/src/modules/puzzle_testmodule_date/puzzle_testmodule_date.ino
@@ -82,7 +82,7 @@ uint8_t read_value_from_date_module(uint8_t bit_order) {
     else
       value |= read_bit << (7 - i);
     digitalWrite(DATE_CLOCK_PIN, HIGH);
-    delay(1);
+    delayMicroseconds(3);
     digitalWrite(DATE_CLOCK_PIN, LOW);
   }
   return value;
@@ -90,7 +90,7 @@ uint8_t read_value_from_date_module(uint8_t bit_order) {
 
 void read_from_date_module(uint8_t* data_out) {
   digitalWrite(DATE_READ_PIN, HIGH);
-  delay(200);
+  delayMicroseconds(3);
   digitalWrite(DATE_READ_PIN, LOW);
 
   for (int i = 0; i < 4; i++) {