diff --git a/cores/arduino/analog.cpp b/cores/arduino/analog.cpp
index 37d3d6cc..a457bc2a 100644
--- a/cores/arduino/analog.cpp
+++ b/cores/arduino/analog.cpp
@@ -645,7 +645,7 @@ void analogReadResolution(int bits) {
     default:
       _analogRequestedReadResolution = 12; 
       adc.cfg.resolution = ADC_RESOLUTION_12_BIT;
-      adc1.cfg.resolution = ADC_RESOLUTION_10_BIT;
+      adc1.cfg.resolution = ADC_RESOLUTION_12_BIT;
       break;
   }