diff --git a/keyboard/hid_liber/matrix.c b/keyboard/hid_liber/matrix.c
index de1790d7..8e373919 100644
--- a/keyboard/hid_liber/matrix.c
+++ b/keyboard/hid_liber/matrix.c
@@ -137,6 +137,10 @@ uint8_t matrix_cols(void)
 
 void matrix_init(void)
 {
+    // To use PORTF disable JTAG with writing JTD bit twice within four cycles.
+    MCUCR |= (1<<JTD);
+    MCUCR |= (1<<JTD);
+
     // initialize row and col
     setup_io_pins();
     setup_leds();