HiFive Unleashed board uses SiFive Freedom U540 as CPU. According to https://www.sifive.com/chip-designer#fu540 https://www.sifive.com/chip-designer#fu540, it u

HiFive Unleashed board uses SiFive Freedom U540 as CPU. According to https://www.sifive.com/chip-designer#fu540 https://www.sifive.com/chip-designer#fu540, it used TSMC 28nm process.