diff --git a/main.c b/main.c
index 3054031..ff2010b 100644
--- a/main.c
+++ b/main.c
@@ -397,7 +397,9 @@ int main(int argc, char *argv[]) {
     disp_drv.draw_buf = &disp_buf;
     disp_drv.hor_res = hor_res;
     disp_drv.ver_res = ver_res;
-    disp_drv.dpi = dpi;
+    if (dpi > 0) {
+        disp_drv.dpi = dpi;
+    }
     lv_disp_drv_register(&disp_drv);
 
     /* Connect input devices */