diff --git a/sys/hps_io.sv b/sys/hps_io.sv
index 92cdf77..e1e166e 100644
--- a/sys/hps_io.sv
+++ b/sys/hps_io.sv
@@ -26,8 +26,13 @@
 // WIDE=1 for 16 bit file I/O
 // VDNUM 1..10
 // BLKSZ 0..7: 0 = 128, 1 = 256, 2 = 512(default), .. 7 = 16384
+
+// F12KEYMOD - is modifier key requested to raise fremework menu? 
+//  0 - no, F12 bring framework menu
+//  1 - F12 is passed to core, F12 + (L/R)GUI key bring framework menu
+
 //
-module hps_io #(parameter CONF_STR, CONF_STR_BRAM=0, PS2DIV=0, WIDE=0, VDNUM=1, BLKSZ=2, PS2WE=0, STRLEN=$size(CONF_STR)>>3)
+module hps_io #(parameter CONF_STR, CONF_STR_BRAM=0, PS2DIV=0, WIDE=0, VDNUM=1, BLKSZ=2, PS2WE=0, STRLEN=$size(CONF_STR)>>3, F12KEYMOD=0)
 (
 	input             clk_sys,
 	inout      [48:0] HPS_BUS,
@@ -334,7 +339,9 @@ always@(posedge clk_sys) begin : uio_block
 				  'h32: io_dout <= gamma_bus[21];
 				  'h36: begin io_dout <= info_n; info_n <= 0; end
 				  'h39: io_dout <= 1;
-				  'h3C: if(upload_req) begin io_dout <= {ioctl_upload_index, 8'd1}; upload_req <= 0; end
+				  'h3C: if(upload_req) begin io_dout <= {ioctl_upload_index, 8'd1}; upload_req <= 0; end				  
+				  'h43: io_dout <= F12KEYMOD;
+				  
 				  'h3E: io_dout <= 1; // shadow mask
 				'h003F: io_dout <= joystick_0_rumble;
 				'h013F: io_dout <= joystick_1_rumble;