diff --git a/sdk/components/pipette_module/pipette_ctrl_module_v2.cpp b/sdk/components/pipette_module/pipette_ctrl_module_v2.cpp
index 52c822a..4152219 100644
--- a/sdk/components/pipette_module/pipette_ctrl_module_v2.cpp
+++ b/sdk/components/pipette_module/pipette_ctrl_module_v2.cpp
@@ -521,6 +521,7 @@ int32_t PipetteModule::do_pipette_aspirate(int32_t ul, int32_t zmotor_v) {
         after_run();
         m_smtp2.pump_stop();
         m_zmotor->getMotor()->stop();
+        // ZLOGI(TAG, "do_pipette_aspirate finish, load_val_ul:%d,m_state.dul:%d before:%d after:%d", m_state.load_val_ul, m_state.dul, m_state.pump_before_pos_ul, m_state.pump_after_pos_ul);
         m_state.load_val_ul = m_state.load_val_ul + m_state.dul;
         if (m_state.load_val_ul < 0) {
           m_state.load_val_ul = 0;
@@ -547,7 +548,10 @@ int32_t PipetteModule::do_pipette_distribut(int32_t ul, int32_t zmotor_v) {
         auto submotor = m_zmotor->getMotor();
         pipette_enable_zmotor(1);
         DO_IN_THREAD(befor_run());
-        DO_IN_THREAD(m_smtp2.pump_distribut(m_config.aspirate_distribut_pump_vel, ul));
+
+        int32_t distribut_ul = ul;
+        if (distribut_ul == 0) distribut_ul = m_state.load_val_ul;
+        DO_IN_THREAD(m_smtp2.pump_distribut(m_config.aspirate_distribut_pump_vel, distribut_ul));
         if (zmotor_v != 0) {
           submotor->moveBy(-LLF_DPOS, zmotor_v);
         }
@@ -718,8 +722,10 @@ int32_t PipetteModule::befor_run() {
   m_smtp2.pump_stop();
   creg.module_status    = 1;
   creg.module_errorcode = 0;
+  m_state.dul           = 0;
   DO(module_active_cfg());
   DO(m_smtp2.pump_get_motor_pos_ul(&m_state.pump_before_pos_ul));
+
   return 0;
 }
 int32_t PipetteModule::after_run() {
diff --git a/sdk/components/sensors/smtp2_v2/smtp2_v2.cpp b/sdk/components/sensors/smtp2_v2/smtp2_v2.cpp
index 2654eda..e92dba4 100644
--- a/sdk/components/sensors/smtp2_v2/smtp2_v2.cpp
+++ b/sdk/components/sensors/smtp2_v2/smtp2_v2.cpp
@@ -30,7 +30,7 @@ bool SMTP2V2::pump_ping() {
 }
 int32_t SMTP2V2::pump_get_state(int32_t* isbusy) {
   size_t rxlen = 0;
-  int    ret   = sendcmd(false /*dump*/, 3 /*retry_times*/, "/1QR\r");
+  int    ret   = sendcmd(false /*dump*/, 5 /*retry_times*/, "/1QR\r");
   if (ret != 0) return ret;
 
   uint8_t errorcode = (uint8_t)m_rxbuf[2];
@@ -63,7 +63,7 @@ int32_t SMTP2V2::pump_get_motor_pos_ul(int32_t* ul) {
   int32_t ret = pump_get_state_as_int(kstate_pump_pos_nl, &nl);
   if (ret != 0) return ret;
 
-  *ul = nl * 1000;
+  *ul = nl / 1000.0 + 0.5;
   return ret;
 }
 
@@ -234,6 +234,7 @@ bool SMTP2V2::sendcmd_auto_retry(bool dump, int auto_retry_times, const char* cm
     if (_sendcmd(dump, cmd)) {
       break;
     }
+    osDelay(10);
     m_rxNum = 0;
     return false;
   }
diff --git a/usrc/project_configs.h b/usrc/project_configs.h
index 45358da..714f791 100644
--- a/usrc/project_configs.h
+++ b/usrc/project_configs.h
@@ -1,5 +1,5 @@
 #pragma once
-#define PC_VERSION           505
+#define PC_VERSION           506
 #define PC_MANUFACTURER      "http://www.iflytop.com/"
 #define PC_PROJECT_NAME      "a8000_subboard"
 #define PC_IFLYTOP_ENABLE_OS 1