Sorry to make another thread but ran into some questions that I would like a definitive answer on. Just to reiterate, this is the board I am referring about : https://numato.com/galatea-pci-express-spartan-6-fpga-development-board/ Firstly, I noticed this on the product desc : "Can be powered from PCIe slot or from an external power supply" Just to confirm, I can run this board outside a machine using the 6 pin on the top right of the board? I have tested this and a led flashes turns on for about a half a second and then turns off. Which I assume is normal. The 3.3v rails on the io expansion seem to be at the correct voltage so I believe I am correct that it is powered correctly. Also, when in a computer, is there any risk if I were to have the 6 pin and pcie plugged in at the same time or can only one be plugged in? The next one is my main quesion about gpio and sorts : When the gpio module is connected to the P4 expansion slot on the board the P2 Header's 1st pin : Based off both product sheets, the Spartan 6 connecting pin would be : D18 correct? Which seems to be aligned with the example project (galateaPCIeGpio) constraints as such (The constraints file on the product page is far clear on the naming) : "NET PORT1 LOC = D18 | IOSTANDARD = "LVCMOS33" | DRIVE = 8 | SLEW = FAST; " This is my main issue, I cannot seem to get a signal out of the gpio board properly. Using basic verilog code such as this : `timescale 1ns / 1ps module testModule #( parameter FAST_TRAIN = "FALSE" ) ( input CLK1, output GPIO_P5 ); assign GPIO_P5 = CLK1; endmodule With constraints as such: CONFIG VCCAUX=3.3; NET "CLK1" LOC = "G9" | IOSTANDARD = "LVCMOS33" | Period = 100 MHz; NET "GPIO_P5" LOC = "H4" | IOSTANDARD = "LVCMOS15" | DRIVE = 8 | SLEW = FAST; # Bank = 3 I don't get a signal coming out of the gpio expansion board attached to the P4 bus on the galatea and I'm hooked up to the P5 header gpio expansion board using pin 1 for this example which as far as I am aware is H4. I have tested this code on another fpga development board I have and it works fine with both running 100 mhz clocks. Some other questions I have are : Is there any way to access lets say the D1 led on the board, the one that seems to light up on power on for a split second? The only schematic reference I found to the D1 led is this : So I'm assuming there is no physical connection to the fpga. Is there any way to access the "SW1" button on the board. Is that this : "#NET "RST_N" LOC = "AB19" | IOSTANDARD = "LVCMOS33" | PULLUP ; # Bank = 2" What is this header for? I just went looking in the schematic to see if I could find it and I'm guessing it is this : Sorry for the long post, just wanted to clear some stuff up. Thanks.