//----------------------------------------------------- // Design Name : General Purpose I/Os // File Name : gpio.v // Coder : Xifan TANG //----------------------------------------------------- //----------------------------------------------------- // Function : A minimum general purpose I/O //----------------------------------------------------- module GPIO ( input A, // Data output output Y, // Data input inout PAD, // bi-directional pad input DIR // direction control ); //----- when direction enabled, the signal is propagated from PAD to data input assign Y = DIR ? PAD : 1'bz; //----- when direction is disabled, the signal is propagated from data out to pad assign PAD = DIR ? 1'bz : A; endmodule //----------------------------------------------------- // Function : A minimum input pad //----------------------------------------------------- module GPIN ( inout A, // External PAD signal output Y // Data input ); assign Y = A; endmodule //----------------------------------------------------- // Function : A minimum output pad //----------------------------------------------------- module GPOUT ( inout Y, // External PAD signal input A // Data output ); assign Y = A; endmodule //----------------------------------------------------- // Function : A minimum embedded I/O // just an overlay to interface other components //----------------------------------------------------- module EMBEDDED_IO ( input SOC_IN, // Input to drive the inpad signal output SOC_OUT, // Output the outpad signal output SOC_DIR, // Output the directionality output FPGA_IN, // Input data to FPGA input FPGA_OUT, // Output data from FPGA input FPGA_DIR // direction control ); assign FPGA_IN = SOC_IN; assign SOC_OUT = FPGA_OUT; assign SOC_DIR = FPGA_DIR; endmodule