diff --git a/ch32v-insert-coin/src/main.rs b/ch32v-insert-coin/src/main.rs
index 8e8a6dc..3414329 100644
--- a/ch32v-insert-coin/src/main.rs
+++ b/ch32v-insert-coin/src/main.rs
@@ -289,7 +289,7 @@ fn app_main(mut p: hal::Peripherals) -> ! {
     // adc2
     // let mut usb_detect_dc = hal::adc::Adc::new(p.ADC1, Default::default());
     let mut usb_detect_pin = p.PD5;
-    let usb_detect_input = Input::new(usb_detect_pin, Pull::Down);
+    let usb_detect_input = Input::new(usb_detect_pin, Pull::Up);
     let usb = Usb::new(usb_detect_input);
 
     // println!("ADC_PIN CHANNEL: {}", adc_pin.channel().channel());