Use rand_core in dependencies, move rand into dev-dependencies for the example.

Author: boondocklabs

Cargo.toml

@@ -20,7 +20,7 @@ stm32-usbd = { version = "0.7.0", optional = true }
 fixed = { version = "1.28.0", optional = true }
 embedded-io = "0.6"
 stm32-hrtim = { version = "0.1.0", optional = true }
-rand = { version = "0.9", default-features = false }
+rand_core = { version = "0.9", default-features = false }
 
 [dependencies.cortex-m]
 version = "0.7.7"
@@ -73,6 +73,7 @@ bme680 = "0.6.0"
 embedded-sdmmc = "0.3.0"
 usb-device = { version = "0.3.2", features = ["defmt"] }
 usbd-serial = "0.2.2"
+rand = { version = "0.9", default-features = false }
 
 #TODO: Separate feature sets
 [features]

src/rng.rs

@@ -1,6 +1,6 @@
 //! True Random Number Generator (TRNG)
 
-use rand::TryRngCore;
+use rand_core::TryRngCore;
 
 use crate::{rcc::Rcc, stm32::RNG};
 use core::{fmt::Formatter, marker::PhantomData};
@@ -27,6 +27,17 @@ impl core::fmt::Display for RngError {
     }
 }
 
+#[cfg(feature = "defmt")]
+impl defmt::Format for RngError {
+    fn format(&self, fmt: defmt::Formatter) {
+        match self {
+            RngError::NotReady => defmt::write!(fmt, "RNG Not ready"),
+            RngError::SeedError => defmt::write!(fmt, "RNG Seed error"),
+            RngError::ClockError => defmt::write!(fmt, "RNG Clock error"),
+        }
+    }
+}
+
 /// Extension trait for the RNG register block
 pub trait RngExt {
     fn constrain(self, rcc: &mut Rcc) -> Rng<Stopped>;