diff --git a/src/driver/drv_ds1820_simple.c b/src/driver/drv_ds1820_simple.c
index f50a2117b..5fa3d108d 100644
--- a/src/driver/drv_ds1820_simple.c
+++ b/src/driver/drv_ds1820_simple.c
@@ -413,7 +413,7 @@ void DS1820_OnEverySecond()
 				// if all is well, it should take 50ms and 100ms
 				// if not, we need to "calibrate" the loop
 				int tempsleep = 5000;
-				int actTick = portTICK_RATE_MS * xTaskGetTickCount();
+				portTickType actTick = portTICK_RATE_MS * xTaskGetTickCount();
 				usleepds(tempsleep);
 				int duration = (int)(portTICK_RATE_MS * xTaskGetTickCount() - actTick);