Add USB serial stdout for RP2040

Builds on the capabilities of the BSP. Unlike the other hardare-specific
packages, I'm using alloc for conveying stdout messages. Check out the
imxrt stdout package for a different approach.

1 files changed, 4 insertions, 3 deletions

diff --git a/crates/rp-pico-2040/src/main.rs b/crates/rp-pico-2040/src/main.rs
index b155870..389257a 100644
--- a/crates/rp-pico-2040/src/main.rs
+++ b/crates/rp-pico-2040/src/main.rs
@@ -3,9 +3,10 @@ use rust_threadx_rp_pico_2040 as _;
 use std::{thread, time::Duration};
 
 fn main() {
-    // Nothing interesting yet. Nevertheless, the LED should
-    // be blinking on a background thread.
+    let mut count = 0_usize;
     loop {
-        thread::sleep(Duration::from_millis(100));
+        println!("Hello world! The count is {count}\r");
+        thread::sleep(Duration::from_millis(1_000));
+        count = count.wrapping_add(1);
     }
 }