diff --git a/components/hardware/uart/zuart_helper.cpp b/components/hardware/uart/zuart_helper.cpp
index 7a07495..d5c97ae 100644
--- a/components/hardware/uart/zuart_helper.cpp
+++ b/components/hardware/uart/zuart_helper.cpp
@@ -19,6 +19,8 @@ ZUARTHelper::ZUARTHelper(const char* tag, UART_HandleTypeDef* uart, DMA_HandleTy
   m_hdma_tx = hdma_tx;
   m_hdma_rx = hdma_rx;
   m_tag     = tag;
+  ZASSERT(hdma_rx->Init.Direction == DMA_PERIPH_TO_MEMORY);
+  ZASSERT(hdma_tx->Init.Direction == DMA_MEMORY_TO_PERIPH);
 }
 
 void ZUARTHelper::cleanRxBuff() {
diff --git a/components/mini_servo_motor/feite_servo_motor.cpp b/components/mini_servo_motor/feite_servo_motor.cpp
index 7854a6c..9a8bb57 100644
--- a/components/mini_servo_motor/feite_servo_motor.cpp
+++ b/components/mini_servo_motor/feite_servo_motor.cpp
@@ -22,10 +22,13 @@ static void dumphex(const char* tag, uint8_t* data, uint8_t len) {
   printf("\n");
 #endif
 }
-void FeiTeServoMotor::initialize2(UART_HandleTypeDef* uart,  DMA_HandleTypeDef* hdma_tx,DMA_HandleTypeDef* hdma_rx) {
+void FeiTeServoMotor::initialize(UART_HandleTypeDef* uart, DMA_HandleTypeDef* hdma_rx, DMA_HandleTypeDef* hdma_tx) {
   m_uart    = uart;
   m_hdma_rx = hdma_rx;
   m_hdma_tx = hdma_tx;
+  ZASSERT(hdma_rx->Init.Direction == DMA_PERIPH_TO_MEMORY);
+  ZASSERT(hdma_tx->Init.Direction == DMA_MEMORY_TO_PERIPH);
+
   m_mutex.init();
 }
 bool FeiTeServoMotor::ping(uint8_t id) {
@@ -366,10 +369,10 @@ bool FeiTeServoMotor::tx_and_rx(uint8_t* tx, uint8_t txdatalen, uint8_t* rx, uin
 
 #if 1
   HAL_UART_Receive_DMA(m_uart, (uint8_t*)rx, expectrxsize);
-  HAL_UART_Transmit(m_uart, tx, txdatalen,1000);
+  HAL_UART_Transmit(m_uart, tx, txdatalen, 1000);
 
   bool overtime_flag = false;
-  while (HAL_UART_GetState(m_uart) != HAL_UART_STATE_READY ) {
+  while (HAL_UART_GetState(m_uart) != HAL_UART_STATE_READY) {
     osDelay(1);
     int rxsize = expectrxsize - __HAL_DMA_GET_COUNTER(m_hdma_rx);
     if (rxsize == expectrxsize) {
diff --git a/components/mini_servo_motor/feite_servo_motor.hpp b/components/mini_servo_motor/feite_servo_motor.hpp
index ca96bd1..f88e1fe 100644
--- a/components/mini_servo_motor/feite_servo_motor.hpp
+++ b/components/mini_servo_motor/feite_servo_motor.hpp
@@ -128,7 +128,7 @@ class FeiTeServoMotor {
   zmutex m_mutex;
 
  public:
-  void initialize2(UART_HandleTypeDef* uart,  DMA_HandleTypeDef* hdma_tx,DMA_HandleTypeDef* hdma_rx);
+  void initialize(UART_HandleTypeDef* uart, DMA_HandleTypeDef* hdma_rx, DMA_HandleTypeDef* hdma_tx);
   bool ping(uint8_t id);
   bool readversion(uint8_t id, uint8_t& mainversion, uint8_t& subversion, uint8_t& miniserv_mainversion, uint8_t& miniserv_subversion);