Add serial I/O to host FPGA

fpga/gpmc/xilinx/common/main.v

@@ -42,6 +42,11 @@ module main(
 	output reg userlogic_reset,
 	input userlogic_clock,
 
+	output userlogic_serial_txd,
+	input userlogic_serial_rxd,
+	output host_serial_txd,
+	input host_serial_rxd,
+
 	input [3:0] four_bit_leds,
 	input [7:0] eight_bit_leds,
 
@@ -57,6 +62,9 @@ module main(
 
 	parameter RAM_ADDR_BITS = 15;
 
+	assign host_serial_txd = userlogic_serial_rxd;
+	assign userlogic_serial_txd = host_serial_rxd;
+
 	reg [15:0] sixteen_bit_io_in;
 	reg [15:0] sixteen_bit_io_out;
 	reg [15:0] sixteen_bit_io_reg;

fpga/gpmc/xilinx/numato/spartan6/xc6slx9/main.ucf

@@ -43,6 +43,11 @@ NET "userproc_done"  LOC = "L13" | IOSTANDARD = "LVCMOS33";
 NET "userlogic_reset" LOC = "E13" | SLEW = FAST | IOSTANDARD = "LVCMOS33";
 NET "userlogic_clock" LOC = "F13" | IOSTANDARD = "LVCMOS33";
 
+NET "userlogic_serial_txd" LOC = "C14" | SLEW = FAST | IOSTANDARD = "LVCMOS33";
+NET "userlogic_serial_rxd" LOC = "D14" | IOSTANDARD = "LVCMOS33";
+NET "host_serial_txd" LOC = "B16" | SLEW = FAST | IOSTANDARD = "LVCMOS33";
+NET "host_serial_rxd" LOC = "A16" | IOSTANDARD = "LVCMOS33";
+
 NET "usermem_data<0>"  LOC = "V14" | SLEW = FAST | IOSTANDARD = "LVCMOS33";
 NET "usermem_data<1>"  LOC = "T11" | SLEW = FAST | IOSTANDARD = "LVCMOS33";
 NET "usermem_data<2>"  LOC = "R11" | SLEW = FAST | IOSTANDARD = "LVCMOS33";