Ever found youself in need to use the NEXYS-4DDR onboard chip, have no idea where to begin? Is existing documentation not very helpful? Tired of probing every pin of the ROM chip figuring out what how the heck to drive that pesky sclk pin? No worries, here's the genuine bonafide electrified ROM controller.

SPI_Controller.vhd is a more generic version of the controller, you can change the OPCODE with any of the opcodes below, ROM_Controller.vhd is a plug and play solution, already preprogrammed with the READ (SPI x1) opcode, see top.vhd how to implement this using the STARTUPE2 generic.

Here's a list of some useful opcodes, you can find more in the S25FL128S documentation =.