diff --git a/src/main.rs b/src/main.rs
index 55d111b..c699b99 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,23 +3,16 @@
 #![feature(type_alias_impl_trait)]
 #![feature(impl_trait_in_assoc_type)]
 
-use ch32_hal::i2c::{self, Duty};
-use ch32_hal::pac::{self, I2C1};
 use ch32_hal::println;
 use ch32_hal::time::Hertz;
 use embassy_executor::Spawner;
-use embassy_time::{Duration, Timer};
+//use embassy_time::{Duration, Timer};
 use hal::bind_interrupts;
-use hal::gpio::{Level, Output};
 use hal::i2c::{Config, I2c, SlaveAddress, SlaveConfig};
-use hal::debug::SDIPrint;
-use hal::peripherals::USBD;
-use hal::usbd::InterruptHandler;
 use {ch32_hal as hal, panic_halt as _};
 
 
 bind_interrupts!(struct Irqs {
-   USB_LP_CAN1_RX0 => InterruptHandler<USBD>;
    I2C1_EV => ch32_hal::i2c::EventInterruptHandler<ch32_hal::peripherals::I2C1>;
    I2C1_ER => ch32_hal::i2c::ErrorInterruptHandler<ch32_hal::peripherals::I2C1>;
 });
@@ -27,7 +20,6 @@ bind_interrupts!(struct Irqs {
 #[embassy_executor::main(entry = "qingke_rt::entry")]
 async fn main(_spawner: Spawner) -> ! {
     let p = hal::init(Default::default());
-    SDIPrint::enable();
 
     let config = Config::default();
     let mut i2c_slave = I2c::new_blocking(p.I2C1, p.PB6, p.PB7, Hertz::khz(100), config)
@@ -37,8 +29,6 @@ async fn main(_spawner: Spawner) -> ! {
         });
 
     loop {
-        Timer::after_millis(10).await;
-
         match i2c_slave.listen_blocking() {
             Ok(command) => {
                 match command {
@@ -46,11 +36,12 @@ async fn main(_spawner: Spawner) -> ! {
                     }
                     ch32_hal::i2c::SlaveCommand::ReadCommand => {
                         // send empty response
-                        let _ = i2c_slave.blocking_write_timeout(&[0x01]);
+                        let _ = i2c_slave.blocking_write_timeout(&[0x05, 0x01]);
                     }
                     ch32_hal::i2c::SlaveCommand::WriteCommand => {
-                        let mut buf: [u8; 1] = [0x0];
+                        let mut buf: [u8; 3] = [0x0, 0x0, 0x0];
                         let _ = i2c_slave.blocking_read_timeout(&mut buf);
+                        println!("received byte 0x{buf:x?}");
                     }
                 }
             },