cyclone IV program device error issue - cyclone IV program device error issue Helo there I have EP4CE6E22C8N Cyclone IV FPGA, Im programing with Quartus prime lite ver 20.0.1 In Quartus all work ok: program with basic OR gate, diagram, simulation (see image 1) & programing board. But my FPGA dont do OR gate My board do AND gate. To "fix" i set NOT gate in input1 & input2 and set NOT gate in Output (see image 2) You know how to fix my board to avoid NOT gates??? Thanks Replies: Re: cyclone IV program device error issue Thanks, I will try other gates to test. Replies: Re: cyclone IV program device error issue LEDs and pushbuttons are usually active low, so when you push both buttons, you're putting 00 into the OR gate, getting a 0 out, which lights the LED. Replies: Re: cyclone IV program device error issue Hi, Thanks for your reply And ofcourse simulation is ok, But FPGA DONT do OR gate, FPGA do AND gate. See the pictures please. You know how FPGA do OR gate if i programing Or gate?? Chers Replies: Re: cyclone IV program device error issue Your simulation for the OR gate is correct. Remember the truth table for an OR gate: 00 | 0 01 | 1 10 | 1 11 | 1 Maybe you're thinking of XOR: 00 | 0 01 | 1 10 | 1 11