1 files changed, 1 insertions, 1 deletions
diff --git a/os/io/adc.h b/os/io/adc.h
index 9c505f66d..08e83caa2 100644
--- a/os/io/adc.h
+++ b/os/io/adc.h
@@ -51,7 +51,7 @@ extern "C" {
   void adcStart(ADCDriver *adcp, const ADCConfig *config);
   void adcStop(ADCDriver *adcp);
   bool_t adcStartConversion(ADCDriver *adcp,
-                            ADCConversionGroup *grpp,
+                            const ADCConversionGroup *grpp,
                             adcsample_t *samples,
                             size_t depth,
                             adccallback_t callback);