Adjust example to properly run.

(Tested)[Rahix#562 (comment)].

Introduces points for other examples commented in.

Author: CoolSlimbo

examples/atmega2560/src/bin/atmega2560-usart_spi-feedback.rs

@@ -36,14 +36,34 @@ fn main() -> ! {
 
     // Create SPI interface.
     let (mut spi, _) = usart_spi::Usart1Spi::new(
-        dp.SPI,
+        dp.USART1,
         pins.pd5.into_output(),
         pins.pd3.into_output(),
         pins.pd2.into_pull_up_input(),
         pins.pd4.into_output().downgrade(),
-        spi::Settings::default(),
+        atmega_hal::spi::Settings::default(),
     );
 
+    /* Other SPI examples for other USART's
+       let (mut spi, _) = usart_spi::Usart2Spi::new(
+           dp.USART2,
+           pins.ph2.into_output(),
+           pins.ph1.into_output(),
+           pins.ph0.into_pull_up_input(),
+           pins.pd4.into_output().downgrade(),
+           atmega_hal::spi::Settings::default(),
+       );
+
+       let (mut spi, _) = usart_spi::Usart3Spi::new(
+           dp.USART3,
+           pins.pj2.into_output(),
+           pins.pj1.into_output(),
+           pins.pj0.into_pull_up_input(),
+           pins.pd4.into_output().downgrade(),
+           atmega_hal::spi::Settings::default(),
+       );
+    */
+
     loop {
         // Send a byte
         let data_out: [u8; 1] = [42];