CDC-ACM USB serial port implementation for usb-device.
CDC-ACM is a USB class that's supported out of the box by most operating systems and used for implementing modems and generic serial ports. The SerialPort class implements a stream-like buffered serial port that can be used similarly to a normal UART.
The crate also contains CdcAcmClass which is a lower-level implementation that has less overhead, but requires more care to use correctly.
A full example requires the use of a hardware-driver, but the hardware independent part is as follows:
let mut serial = SerialPort::new(&usb_bus);
let mut usb_dev = UsbDeviceBuilder::new(&usb_bus, UsbVidPid(0x16c0, 0x27dd))
.product("Serial port")
.device_class(USB_CLASS_CDC)
.build();
loop {
if !usb_dev.poll(&mut [&mut serial]) {
continue;
}
let mut buf = [0u8; 64];
match serial.read(&mut buf[..]) {
Ok(count) => {
// count bytes were read to &buf[..count]
},
Err(UsbError::WouldBlock) => // No data received
Err(err) => // An error occurred
};
match serial.write(&[0x3a, 0x29]) {
Ok(count) => {
// count bytes were written
},
Err(UsbError::WouldBlock) => // No data could be written (buffers full)
Err(err) => // An error occurred
};
}