diff --git a/tests/test/support/ehci_controller.c b/tests/test/support/ehci_controller.c
index fed3c730..0bc09f53 100644
--- a/tests/test/support/ehci_controller.c
+++ b/tests/test/support/ehci_controller.c
@@ -76,3 +76,13 @@ void ehci_controller_run(uint8_t hostid)
 
   regs->usb_sts = EHCI_INT_MASK_NXP_ASYNC;
 }
+
+void ehci_controller_device_plug(uint8_t hostid, tusb_speed_t speed)
+{
+  ehci_registers_t* const regs = get_operational_register(hostid);
+
+  regs->usb_sts_bit.port_change_detect = 1;
+  regs->portsc_bit.connect_status_change = 1;
+  regs->portsc_bit.current_connect_status = 1;
+  regs->portsc_bit.nxp_port_speed = speed;
+}
diff --git a/tests/test/support/ehci_controller.h b/tests/test/support/ehci_controller.h
index 945e8e13..aee3f011 100644
--- a/tests/test/support/ehci_controller.h
+++ b/tests/test/support/ehci_controller.h
@@ -56,6 +56,7 @@
 #endif
 
 void ehci_controller_run(uint8_t hostid);
+void ehci_controller_device_plug(uint8_t hostid, tusb_speed_t speed);
 
 #ifdef __cplusplus
  }
diff --git a/tinyusb/host/ehci/ehci.c b/tinyusb/host/ehci/ehci.c
index 2fefed23..6caf1e71 100644
--- a/tinyusb/host/ehci/ehci.c
+++ b/tinyusb/host/ehci/ehci.c
@@ -134,6 +134,32 @@ tusb_error_t hcd_init(void)
   return TUSB_ERROR_NONE;
 }
 
+//--------------------------------------------------------------------+
+// PORT API
+//--------------------------------------------------------------------+
+void hcd_port_reset(uint8_t hostid)
+{
+  ehci_registers_t* const regs = get_operational_register(hostid);
+
+  regs->portsc_bit.port_enable = 0; // disable port before reset
+  regs->portsc_bit.port_reset = 1;
+
+#ifndef _TEST_
+  // NXP specific, port reset will automatically be 0 when reset sequence complete
+  while( regs->portsc_bit.port_reset || !regs->portsc_bit.port_enable){}
+#endif
+}
+
+bool hcd_port_connect_status(uint8_t hostid)
+{
+  return false;
+}
+
+tusb_speed_t hcd_port_speed(uint8_t hostid)
+{
+  return TUSB_SPEED_HIGH;
+}
+
 //--------------------------------------------------------------------+
 // EHCI Interrupt Handler
 //--------------------------------------------------------------------+
@@ -143,6 +169,22 @@ static inline uint8_t get_qhd_index(ehci_qhd_t * p_qhd)
   return p_qhd - ehci_data.device[p_qhd->device_address].qhd;
 }
 
+
+void port_connect_status_isr(uint8_t hostid)
+{
+  ehci_registers_t* const regs = get_operational_register(hostid);
+
+  if (regs->portsc_bit.current_connect_status) // device plugged
+  {
+    hcd_port_reset(hostid);
+    usbh_device_plugged_isr(hostid, regs->portsc_bit.nxp_port_speed); // NXP specific port speed
+  }else // device unplugged
+  {
+//    usbh_device_
+  }
+
+}
+
 void async_list_process_isr(ehci_qhd_t * const async_head, ehci_registers_t * const regs)
 {
   ehci_qhd_t *p_qhd = async_head;
@@ -183,7 +225,6 @@ void async_list_process_isr(ehci_qhd_t * const async_head, ehci_registers_t * co
 }
 
 //------------- Host Controller Driver's Interrupt Handler -------------//
-// TODO this isr is not properly go through TDD
 void hcd_isr(uint8_t hostid)
 {
   ehci_registers_t* const regs = get_operational_register(hostid);
@@ -211,7 +252,14 @@ void hcd_isr(uint8_t hostid)
 
   if (int_status & EHCI_INT_MASK_PORT_CHANGE)
   {
-//    port_status_change_isr(h)
+    printf("%s %d\n", __PRETTY_FUNCTION__, __LINE__);
+    if (regs->portsc_bit.connect_status_change)
+    {
+      printf("%s %d\n", __PRETTY_FUNCTION__, __LINE__);
+      port_connect_status_isr(hostid);
+    }
+
+    regs->portsc |= EHCI_PORTSC_MASK_ALL; // Acknowledge all the change bit in portsc
   }
 
   if (int_status & EHCI_INT_MASK_ASYNC_ADVANCE)
@@ -323,19 +371,6 @@ tusb_error_t hcd_controller_reset(uint8_t hostid)
   return timeout_expired(&timeout) ? TUSB_ERROR_OSAL_TIMEOUT : TUSB_ERROR_NONE;
 }
 
-//--------------------------------------------------------------------+
-// PORT API
-//--------------------------------------------------------------------+
-bool hcd_port_connect_status(uint8_t core_id)
-{
-  return false;
-}
-
-tusb_speed_t hcd_port_speed(uint8_t core_id)
-{
-  return TUSB_SPEED_HIGH;
-}
-
 //--------------------------------------------------------------------+
 // PIPE API
 //--------------------------------------------------------------------+
diff --git a/tinyusb/host/ehci/ehci.h b/tinyusb/host/ehci/ehci.h
index cd03c2b9..bceb78e7 100644
--- a/tinyusb/host/ehci/ehci.h
+++ b/tinyusb/host/ehci/ehci.h
@@ -327,6 +327,17 @@ enum ehci_usbcmd_pos_ {
   EHCI_USBCMD_POS_INTERRUPT_THRESHOLD    = 16
 };
 
+enum ehci_portsc_change_mask_{
+  EHCI_PORTSC_MASK_CONNECT_STATUS_CHANGE = BIT_(1),
+  EHCI_PORTSC_MASK_PORT_ENABLE_CHAGNE = BIT_(3),
+  EHCI_PORTSC_MASK_OVER_CURRENT_CHANGE = BIT_(5),
+
+  EHCI_PORTSC_MASK_ALL =
+      EHCI_PORTSC_MASK_CONNECT_STATUS_CHANGE |
+      EHCI_PORTSC_MASK_PORT_ENABLE_CHAGNE |
+      EHCI_PORTSC_MASK_OVER_CURRENT_CHANGE
+};
+
 typedef volatile struct {
   union {
     uint32_t usb_cmd                  ; ///< The Command Register indicates the command to be executed by the serial bus host controller. Writing to the register causes a command to be executed
diff --git a/tinyusb/host/usbh.c b/tinyusb/host/usbh.c
index f0b79dab..05234aad 100644
--- a/tinyusb/host/usbh.c
+++ b/tinyusb/host/usbh.c
@@ -47,10 +47,14 @@
 #include "tusb.h"
 #include "usbh_hcd.h"
 
+//TODO temporarily
+#if TUSB_CFG_OS == TUSB_OS_NONE && !defined(_TEST_)
 void tusb_tick_tock(void)
 {
   osal_tick_tock();
 }
+#endif
+
 //--------------------------------------------------------------------+
 // MACRO CONSTANT TYPEDEF
 //--------------------------------------------------------------------+
@@ -129,21 +133,6 @@ tusb_error_t usbh_init(void)
   return TUSB_ERROR_NONE;
 }
 
-// interrupt caused by a TD (with IOC=1) in pipe of class class_code
-void usbh_isr(pipe_handle_t pipe_hdl, uint8_t class_code)
-{
-  if (class_code == 0) // Control transfer
-  {
-    // TODO some semaphore posting
-  }else if (usbh_class_drivers[class_code].isr)
-  {
-    usbh_class_drivers[class_code].isr(pipe_hdl);
-  }else
-  {
-    ASSERT(false, (void) 0); // something wrong, no one claims the isr's source
-  }
-}
-
 // function called within a task, requesting os blocking services, subtask input parameter must be static/global variables
 tusb_error_t usbh_control_xfer_subtask(uint8_t dev_addr, tusb_std_request_t const* p_request, uint8_t* data)
 {
@@ -174,6 +163,35 @@ pipe_status_t usbh_pipe_status_get(pipe_handle_t pipe_hdl)
   return PIPE_STATUS_BUSY;
 }
 
+//--------------------------------------------------------------------+
+// USBH-HCD ISR/Callback API
+//--------------------------------------------------------------------+
+// interrupt caused by a TD (with IOC=1) in pipe of class class_code
+void usbh_isr(pipe_handle_t pipe_hdl, uint8_t class_code)
+{
+  if (class_code == 0) // Control transfer
+  {
+    // TODO some semaphore posting
+  }else if (usbh_class_drivers[class_code].isr)
+  {
+    usbh_class_drivers[class_code].isr(pipe_hdl);
+  }else
+  {
+    ASSERT(false, (void) 0); // something wrong, no one claims the isr's source
+  }
+}
+
+void usbh_device_plugged_isr(uint8_t hostid, tusb_speed_t speed)
+{
+
+}
+
+void usbh_device_unplugged_isr(uint8_t hostid)
+{
+
+}
+
+
 //--------------------------------------------------------------------+
 // ENUMERATION TASK
 //--------------------------------------------------------------------+
diff --git a/tinyusb/host/usbh_hcd.h b/tinyusb/host/usbh_hcd.h
index 03901050..bbcad361 100644
--- a/tinyusb/host/usbh_hcd.h
+++ b/tinyusb/host/usbh_hcd.h
@@ -101,6 +101,9 @@ typedef struct { // TODO internal structure, re-order members
 extern usbh_device_info_t usbh_device_info_pool[TUSB_CFG_HOST_DEVICE_MAX+1]; // including zero-address
 
 void usbh_isr(pipe_handle_t pipe_hdl, uint8_t class_code);
+void usbh_device_plugged_isr(uint8_t hostid, tusb_speed_t speed);
+void usbh_device_unplugged_isr(uint8_t hostid);
+
 
 #ifdef __cplusplus
  }