rust-osdev / uart_16550

Minimal support for uart_16550 serial output.
MIT License
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uart_16550

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Minimal support for serial communication through UART devices, which are compatible to the 16550 UART. This crate supports I/O port-mapped (x86 only) and memory-mapped UARTS.

Usage

Depending on the system architecture, the UART can be either accessed through port-mapped I/O or memory-mapped I/O.

With port-mappd I/O

The UART is accessed through port-mapped I/O on architectures such as x86_64. On these architectures, the SerialPort type can be used:

use uart_16550::SerialPort;

const SERIAL_IO_PORT: u16 = 0x3F8;

let mut serial_port = unsafe { SerialPort::new(SERIAL_IO_PORT) };
serial_port.init();

// Now the serial port is ready to be used. To send a byte:
serial_port.send(42);

// To receive a byte:
let data = serial_port.receive();

With memory mapped serial port

Most other architectures, such as RISC-V, use memory-mapped I/O for accessing the UARTs. On these architectures, the MmioSerialPort type can be used:

use uart_16550::MmioSerialPort;

const SERIAL_PORT_BASE_ADDRESS: usize = 0x1000_0000;

let mut serial_port = unsafe { MmioSerialPort::new(SERIAL_PORT_BASE_ADDRESS) };
serial_port.init();

// Now the serial port is ready to be used. To send a byte:
serial_port.send(42);

// To receive a byte:
let data = serial_port.receive();

Building with stable rust

This needs to have the compile-time requirements of the cc crate installed on your system. It was currently only tested on Linux and MacOS.

License

Licensed under the MIT license (LICENSE or http://opensource.org/licenses/MIT).