diff --git a/client/proxmark3.c b/client/proxmark3.c
index 78bc1fe47..ef3d33e82 100644
--- a/client/proxmark3.c
+++ b/client/proxmark3.c
@@ -200,6 +200,7 @@ int main(int argc, char* argv[]) {
   
   if (argc < 2) {
     printf("syntax: %s <port>\n\n",argv[0]);
+    printf("\tLinux example:'%s /dev/ttyACM0'\n\n", argv[0]);
     return 1;
   }