diff --git a/src/hardware/keyboard.cpp b/src/hardware/keyboard.cpp
index c73f585e..23d9395d 100644
--- a/src/hardware/keyboard.cpp
+++ b/src/hardware/keyboard.cpp
@@ -197,6 +197,7 @@ static void write_p60(Bit32u port,Bit8u val) {
 
 static Bit8u read_p61(Bit32u port) {
 	port_61_data^=0x20;
+	port_61_data^=0x10;
 	return port_61_data;
 }