UART RusPiRo crate
This crate provides access to the Uart0(Pl011) and Uart1 (miniUART) peripheral of the Raspberry Pi. This is quite helpful during bare metal development to use a terminal console connected to the miniUART of the Raspberry Pi to get some debug information printed while the program is executed on the device. Especialy if the program is in a state where there is no other output option and blinking LEDs are not sufficient.
Usage
To use the crate just add the following dependency to your Cargo.toml
file:
[dependencies]
ruspiro-uart = "0.2"
Once done the access to the UART abstraction is available in your rust files like so:
use ruspiro_uart::Uart1;
fn demo() {
let mut uart = Uart1::new();
if uart.initialize(250_000_000, 115_200).is_ok() {
uart.send_string("This is some string");
}
}
In this example the Uart1 will be no longer be available once it goes out of scope. Whichs makes it a bit cumbersome to use it in a real world example. Therefore the proposed usage of the UART is to use it as a generic console output channel. To do so, please refer to the ruspiro-console crate. But in case you would like to use the uart without the console abstraction it is recommended to wrap it into a singleton to guaranty safe cross core access and only 1 time initialization. In the example we pass a fixed core clock rate to the initialization function. However, the real core clock rate could be optained with a call to the mailbox property tag interface of the Raspberry Pi (see ruspiro-mailbox for details.). This mailbox crate is not linked into the Uart crate to ensure usability of this crate with as less dependencies as possible.
use ruspiro_singleton::Singleton; // don't forget the dependency to be setup
use ruspiro_uart::Uart1;
static UART: Singleton<Uart1> = Singleton::new(Uart1::new());
fn demo() {
let _ = UART.take_for(|uart| uart.initialize(250_000_000, 115_200)).expect("unable to init uart1");
print_something("Hello Uart...");
}
fn print_something(s: &str) {
UART.take_for(|uart| uart.send_string(s));
}
License
Licensed under Apache License, Version 2.0, (LICENSE or http://www.apache.org/licenses/LICENSE-2.0)