main: fix wfi, revise leds, unreachable end

src/main.rs

@@ -105,36 +105,39 @@ fn main() -> ! {
         Server::run(iface, |server| {
             let mut last_output = 0_u32;
             loop {
-                led_green.on();
                 let now = timer::now().0;
                 let instant = Instant::from_millis(now as i64);
-                server.poll(instant);
-                led_green.off();
-
                 led_blue.on();
+                cortex_m::interrupt::free(net::clear_pending);
+                server.poll(instant)
+                    .unwrap_or_else(|e| {
+                        warn!("poll: {:?}", e);
+                    });
+                led_blue.off();
+
                 let now = timer::now().0;
                 if now - last_output >= OUTPUT_INTERVAL {
+                    led_red.on();
                     let adc_value = adc_input.read();
                     write!(server, "t={},pa3={}\r\n", now, adc_value).unwrap();
                     last_output = now;
+                    led_red.off();
                 }
-                led_blue.off();
 
                 // Update watchdog
                 wd.feed();
 
-                led_red.on();
                 cortex_m::interrupt::free(|cs| {
                     if !net::is_pending(cs) {
+                        led_green.on();
                         // Wait for interrupts
                         wfi();
-                        net::clear_pending(cs);
+                        led_green.off();
                     }
                 });
-                led_red.off();
             }
         });
     });
 
-    unimplemented!()
+    unreachable!()
 }