diff --git a/plsr/pulse_driver/plsr_pulse_driver.c b/plsr/pulse_driver/plsr_pulse_driver.c
index fa0bca3..73007e2 100644
--- a/plsr/pulse_driver/plsr_pulse_driver.c
+++ b/plsr/pulse_driver/plsr_pulse_driver.c
@@ -73,6 +73,44 @@ static void PlsrPulseDriverDirGpioInit(void)
     HAL_GPIO_WritePin(PLSR_Y3_PORT, PLSR_Y3_PIN, GPIO_PIN_RESET);
 }
 
+/**
+ * 停表：不关复用、不关 CC1E。
+ * HAL_TIM_PWM_Stop 会清 CC1E，脚变成 AF 高阻，飞线接地的沿会耦合出极短脉冲。
+ * Forced active + 通道保持使能：TIM 推挽把脚主动拉高（段间空闲高）。
+ */
+static void PlsrPulseDriverOcHoldHigh(TIM_HandleTypeDef *htim)
+{
+    uint32_t ccmr;
+
+    if ((htim == (TIM_HandleTypeDef *)0) || (htim->Instance == (TIM_TypeDef *)0))
+    {
+        return;
+    }
+
+    __HAL_TIM_DISABLE_IT(htim, TIM_IT_UPDATE);
+    htim->Instance->CR1 &= (uint32_t)(~(TIM_CR1_CEN | TIM_CR1_OPM));
+
+    ccmr = htim->Instance->CCMR1;
+    ccmr &= (uint32_t)(~TIM_CCMR1_OC1M);
+    ccmr |= TIM_OCMODE_FORCED_ACTIVE;
+    htim->Instance->CCMR1 = ccmr;
+    htim->Instance->CCER |= TIM_CCER_CC1E;
+
+    __HAL_TIM_CLEAR_FLAG(htim, TIM_FLAG_UPDATE);
+    __HAL_TIM_CLEAR_IT(htim, TIM_IT_UPDATE);
+    TIM_CHANNEL_STATE_SET(htim, TIM_CHANNEL_1, HAL_TIM_CHANNEL_STATE_READY);
+}
+
+static void PlsrPulseDriverOcPwm1(TIM_HandleTypeDef *htim)
+{
+    uint32_t ccmr;
+
+    ccmr = htim->Instance->CCMR1;
+    ccmr &= (uint32_t)(~TIM_CCMR1_OC1M);
+    ccmr |= TIM_OCMODE_PWM1;
+    htim->Instance->CCMR1 = ccmr;
+}
+
 void HAL_TIM_PWM_MspInit(TIM_HandleTypeDef *htim)
 {
     GPIO_InitTypeDef gpio = {0};
@@ -80,7 +118,7 @@ void HAL_TIM_PWM_MspInit(TIM_HandleTypeDef *htim)
     __HAL_RCC_GPIOF_CLK_ENABLE();
 
     gpio.Mode = GPIO_MODE_AF_PP;
-    gpio.Pull = GPIO_PULLDOWN;
+    gpio.Pull = GPIO_PULLUP;
     gpio.Speed = GPIO_SPEED_FREQ_HIGH;
 
     if (htim->Instance == TIM10)
@@ -123,6 +161,8 @@ static void PlsrPulseDriverTimInitOne(TIM_HandleTypeDef *htim, TIM_TypeDef *inst
         Error_Handler();
     }
     htim->Instance->CCMR1 |= TIM_CCMR1_OC1PE;
+    /* 复用保持：比较通道强制有效，推挽把脚拉高 */
+    PlsrPulseDriverOcHoldHigh(htim);
 }
 
 void PlsrPulseDriverInit(void)
@@ -315,14 +355,7 @@ void PlsrPulseDriverUnlockPsc(void)
 
 static void PlsrPulseDriverStopHtim(TIM_HandleTypeDef *htim)
 {
-    if (htim == (TIM_HandleTypeDef *)0)
-    {
-        return;
-    }
-    __HAL_TIM_DISABLE_IT(htim, TIM_IT_UPDATE);
-    (void)HAL_TIM_PWM_Stop(htim, TIM_CHANNEL_1);
-    __HAL_TIM_CLEAR_FLAG(htim, TIM_FLAG_UPDATE);
-    __HAL_TIM_CLEAR_IT(htim, TIM_IT_UPDATE);
+    PlsrPulseDriverOcHoldHigh(htim);
 }
 
 static void PlsrPulseDriverStartCommon(uint32_t freq_hz, uint8_t enable_update_it)
@@ -377,24 +410,18 @@ static void PlsrPulseDriverStartCommon(uint32_t freq_hz, uint8_t enable_update_i
     __HAL_TIM_SET_COUNTER(htim, 0U);
 
     /*
-     * UG 把新 PSC/ARR/CCR 从影寄存器载入现行寄存器。
-     * 它会置 UIF → 若先开 IT 会进一次假 ISR（多计一拍）。
-     * 顺序：UG → 清 UIF → Start PWM → 开 IT。
+     * UG 在 Forced active 下做：脚保持高，避免 UG 在 PWM 复用脚上打出针。
+     * 再切回 PWM1 并开计数。
      */
+    PlsrPulseDriverOcHoldHigh(htim);
     htim->Instance->EGR = TIM_EGR_UG;
     __HAL_TIM_CLEAR_FLAG(htim, TIM_FLAG_UPDATE);
     __HAL_TIM_CLEAR_IT(htim, TIM_IT_UPDATE);
 
-    if (HAL_TIM_PWM_Start(htim, TIM_CHANNEL_1) != HAL_OK)
-    {
-        TIM_CHANNEL_STATE_SET(htim, TIM_CHANNEL_1, HAL_TIM_CHANNEL_STATE_READY);
-        (void)HAL_TIM_PWM_Start(htim, TIM_CHANNEL_1);
-    }
+    PlsrPulseDriverOcPwm1(htim);
+    htim->Instance->CCER |= TIM_CCER_CC1E;
+    __HAL_TIM_ENABLE(htim);
 
-    /*
-     * 清一次 UIF（Start 可能再触发 UG/UIF），然后才开中断。
-     * 确保第一个真脉冲完成后才进 ISR，不多计。
-     */
     __HAL_TIM_CLEAR_FLAG(htim, TIM_FLAG_UPDATE);
     __HAL_TIM_CLEAR_IT(htim, TIM_IT_UPDATE);