1 files changed, 5 insertions, 5 deletions

diff --git a/co2.h b/co2.h
index ee4f6f2..f75c94c 100644
--- a/co2.h
+++ b/co2.h
@@ -23,14 +23,14 @@ public:
     // stop potentially previously started measurement
     error = scd4x.stopPeriodicMeasurement();
     if (error) {
-        Serial.print("CO2 stopPeriodicMeasurement() error: ");
+        Serial.print("! CO2 stopPeriodicMeasurement() error: ");
         errorToString(error, errorMessage, 256);
         Serial.println(errorMessage);
     }
 
     error = scd4x.setAutomaticSelfCalibration(1);
     if (error) {
-        Serial.print("CO2 setAutomaticSelfCalibration() error: ");
+        Serial.print("! CO2 setAutomaticSelfCalibration() error: ");
         errorToString(error, errorMessage, 256);
         Serial.println(errorMessage);
     }
@@ -38,7 +38,7 @@ public:
     // Start Measurement
     error = scd4x.startLowPowerPeriodicMeasurement();
     if (error) {
-        Serial.print("CO2 startLowPowerPeriodicMeasurement() error: ");
+        Serial.print("! CO2 startLowPowerPeriodicMeasurement() error: ");
         errorToString(error, errorMessage, 256);
         Serial.println(errorMessage);
     }
@@ -51,7 +51,7 @@ public:
 
     error = scd4x.getDataReadyStatus(ready);
     if (error) {
-        Serial.print("CO2 getDataReadyStatus() error: ");
+        Serial.print("! CO2 getDataReadyStatus() error: ");
         errorToString(error, errorMessage, 256);
         Serial.println(errorMessage);
         return false;
@@ -67,7 +67,7 @@ public:
 
     error = scd4x.readMeasurement(data->co2, data->temperature, data->humidity);
     if (error) {
-        Serial.print("CO2 readMeasurement() error: ");
+        Serial.print("! CO2 readMeasurement() error: ");
         errorToString(error, errorMessage, 256);
         Serial.println(errorMessage);
     }