from time import sleep from amaranth import * from amaranth.lib import io from manta import * class UARTIOCoreExample(Elaboratable): def __init__(self, platform, port): self.platform = platform # Create Manta instance self.manta = Manta() # Configure it to communicate over UART self.manta.interface = UARTInterface( port=port, baudrate=2000000, clock_freq=platform.default_clk_frequency, ) # Autodetect the number of LEDs on the platform resources = platform.resources.keys() self.n_leds = len([name for name, _ in resources if name == "led"]) # Add IOCore to Manta instance self.leds = Signal(self.n_leds) self.manta.cores.io = IOCore(outputs=[self.leds]) def elaborate(self, platform): m = Module() # Add Manta as a submodule m.submodules.manta = self.manta # Wire each LED to Manta's IO Core output for i in range(self.n_leds): led = io.Buffer("o", platform.request("led", i, dir="-")) m.d.comb += led.o.eq(self.leds[i]) m.submodules += led # Wire UART pins to the Manta instance uart_pins = platform.request("uart", dir={"tx": "-", "rx": "-"}) m.submodules.uart_rx = uart_rx = io.Buffer("i", uart_pins.rx) m.submodules.uart_tx = uart_tx = io.Buffer("o", uart_pins.tx) m.d.comb += self.manta.interface.rx.eq(uart_rx.i) m.d.comb += uart_tx.o.eq(self.manta.interface.tx) return m def test(self): # Build and program the FPGA self.platform.build(self, do_program=True) # Iterate through all the LEDs, blinking them off and on i = 0 while True: self.manta.cores.io.set_probe("leds", 1 << i) i = (i + 1) % self.n_leds sleep(0.1) # Amaranth has a built-in build system, and well as a set of platform # definitions for a huge number of FPGA boards. The class defined above is # very generic, as it specifies a design independent of any particular FGPA # board. This means that by changing which platform you pass UARTIOCoreExample # below, you can port this example to any FPGA board! if __name__ == "__main__": from amaranth_boards.icestick import ICEStickPlatform UARTIOCoreExample(platform=ICEStickPlatform(), port="auto").test()