Dream Theater - In The Presence of Enemies intro on FPGA

[muhonzen]

Do you use any GPIO+timer interrupt for that? Or is that a special output port?

[tvanas]

The design doesn't use any software interrupts (no software at all for that matter). A custom sequencer (a simple clock divider) generates pulses for the synthesizer. A square wave signal with the corresponding frequency is presented at a regular IO pin indeed.