diff --git a/doc/new_frame_format.md b/doc/new_frame_format.md
index 6075fb2c9..102ef9c18 100644
--- a/doc/new_frame_format.md
+++ b/doc/new_frame_format.md
@@ -373,9 +373,9 @@ It was needed to tune pm3 RX usart `maxtry` :
     time client/proxmark3 -p /dev/ttyUSB0 -b 115200 -c "lf read"
     6.28s
 
-    time client/proxmark3 -p /dev/ttyACM0 -c "mem dump f foo_usb"
+    time client/proxmark3 -p /dev/ttyACM0 -c "mem dump -f foo_usb"
     1.48s
-    time client/proxmark3 -p /dev/ttyUSB0 -b 115200 -c "mem dump f foo_fpc"
+    time client/proxmark3 -p /dev/ttyUSB0 -b 115200 -c "mem dump -f foo_fpc"
     25.34s