enable a20

defines.s

@@ -11,6 +11,18 @@
 %define VGA_WIDTH  80
 %define VGA_HEIGHT 25
 
+%define INTEL_8042_IO_DATA   0x60
+%define INTEL_8042_IN_STATUS 0x64
+%define INTEL_8042_OUT_CMD   0x64
+
+%define INTEL_8042_STATUS_OBUF 0
+%define INTEL_8042_STATUS_IBUF 1
+
+%define INTEL_8042_CMD_PS2_1_DISABLE             0xad
+%define INTEL_8042_CMD_PS2_1_ENABLE              0xae
+%define INTEL_8042_CMD_CONTROLLER_OUT_PORT_READ  0xd0
+%define INTEL_8042_CMD_CONTROLLER_OUT_PORT_WRITE 0xd1
+
 ; boot0 base stack frame variable offsets / globals
 ; (we use the same offsets once we copy the variables to the globals section)
 ; -------------------------------------------------------------------------------------------------