diff --git a/src/host/ehci/ehci.c b/src/host/ehci/ehci.c
index abf5e561..d30b68a6 100644
--- a/src/host/ehci/ehci.c
+++ b/src/host/ehci/ehci.c
@@ -287,7 +287,7 @@ tusb_error_t  hcd_pipe_control_open(uint8_t dev_addr, uint8_t max_packet_size)
   if (dev_addr != 0)
   {
     //------------- insert to async list -------------//
-    list_insert( (ehci_link_t*) get_async_head(usbh_devices[dev_addr].core_id),
+    list_insert( (ehci_link_t*) get_async_head(_usbh_devices[dev_addr].core_id),
                  (ehci_link_t*) p_qhd, EHCI_QUEUE_ELEMENT_QHD);
   }
 
@@ -344,7 +344,7 @@ tusb_error_t  hcd_pipe_control_close(uint8_t dev_addr)
 
   if (dev_addr != 0)
   {
-    TU_ASSERT_ERR( list_remove_qhd( (ehci_link_t*) get_async_head( usbh_devices[dev_addr].core_id ),
+    TU_ASSERT_ERR( list_remove_qhd( (ehci_link_t*) get_async_head( _usbh_devices[dev_addr].core_id ),
                                     (ehci_link_t*) p_qhd) );
   }
 
@@ -376,12 +376,12 @@ pipe_handle_t hcd_pipe_open(uint8_t dev_addr, tusb_desc_endpoint_t const * p_end
 
   if (p_endpoint_desc->bmAttributes.xfer == TUSB_XFER_BULK)
   {
-    list_head = (ehci_link_t*) get_async_head(usbh_devices[dev_addr].core_id);
+    list_head = (ehci_link_t*) get_async_head(_usbh_devices[dev_addr].core_id);
   }
   #if EHCI_PERIODIC_LIST // TODO refractor/group this together
   else if (p_endpoint_desc->bmAttributes.xfer == TUSB_XFER_INTERRUPT)
   {
-    list_head = get_period_head(usbh_devices[dev_addr].core_id, p_qhd->interval_ms);
+    list_head = get_period_head(_usbh_devices[dev_addr].core_id, p_qhd->interval_ms);
   }
   #endif
 
@@ -443,14 +443,14 @@ tusb_error_t  hcd_pipe_close(pipe_handle_t pipe_hdl)
   if ( pipe_hdl.xfer_type == TUSB_XFER_BULK )
   {
     TU_ASSERT_ERR( list_remove_qhd(
-        (ehci_link_t*) get_async_head( usbh_devices[pipe_hdl.dev_addr].core_id ),
+        (ehci_link_t*) get_async_head( _usbh_devices[pipe_hdl.dev_addr].core_id ),
         (ehci_link_t*) p_qhd) );
   }
   #if EHCI_PERIODIC_LIST // TODO refractor/group this together
   else
   {
     TU_ASSERT_ERR( list_remove_qhd(
-        get_period_head( usbh_devices[pipe_hdl.dev_addr].core_id, p_qhd->interval_ms ),
+        get_period_head( _usbh_devices[pipe_hdl.dev_addr].core_id, p_qhd->interval_ms ),
         (ehci_link_t*) p_qhd) );
   }
   #endif
@@ -505,7 +505,7 @@ static void async_advance_isr(ehci_qhd_t * const async_head)
     async_head->p_qtd_list_head    = async_head->p_qtd_list_tail = NULL;
     async_head->qtd_overlay.halted = 1;
 
-    usbh_devices[0].state          = TUSB_DEVICE_STATE_UNPLUG;
+    _usbh_devices[0].state          = TUSB_DEVICE_STATE_UNPLUG;
   }
 
   for(uint8_t relative_dev_addr=0; relative_dev_addr < CFG_TUSB_HOST_DEVICE_MAX; relative_dev_addr++)
@@ -518,7 +518,7 @@ static void async_advance_isr(ehci_qhd_t * const async_head)
       p_control_qhd->used        = 0;
 
       // Host Controller has cleaned up its cached data for this device, set state to unplug
-      usbh_devices[relative_dev_addr+1].state = TUSB_DEVICE_STATE_UNPLUG;
+      _usbh_devices[relative_dev_addr+1].state = TUSB_DEVICE_STATE_UNPLUG;
 
       for (uint8_t i=0; i<HCD_MAX_ENDPOINT; i++) // free all qhd
       {
@@ -833,7 +833,7 @@ static inline ehci_link_t* get_period_head(uint8_t hostid, uint8_t interval_ms)
 static inline ehci_qhd_t* get_control_qhd(uint8_t dev_addr)
 {
   return (dev_addr == 0) ?
-      get_async_head( usbh_devices[dev_addr].core_id ) :
+      get_async_head( _usbh_devices[dev_addr].core_id ) :
       &ehci_data.device[dev_addr-1].control.qhd;
 }
 static inline ehci_qtd_t* get_control_qtds(uint8_t dev_addr)
@@ -942,7 +942,7 @@ static void qhd_init(ehci_qhd_t *p_qhd, uint8_t dev_addr, uint16_t max_packet_si
   p_qhd->device_address                   = dev_addr;
   p_qhd->non_hs_period_inactive_next_xact = 0;
   p_qhd->endpoint_number                  = endpoint_addr & 0x0F;
-  p_qhd->endpoint_speed                   = usbh_devices[dev_addr].speed;
+  p_qhd->endpoint_speed                   = _usbh_devices[dev_addr].speed;
   p_qhd->data_toggle_control              = (xfer_type == TUSB_XFER_CONTROL) ? 1 : 0;
   p_qhd->head_list_flag                   = (dev_addr == 0) ? 1 : 0; // addr0's endpoint is the static asyn list head
   p_qhd->max_package_size                 = max_packet_size;
@@ -979,8 +979,8 @@ static void qhd_init(ehci_qhd_t *p_qhd, uint8_t dev_addr, uint16_t max_packet_si
     p_qhd->interrupt_smask = p_qhd->non_hs_interrupt_cmask = 0;
   }
 
-  p_qhd->hub_address             = usbh_devices[dev_addr].hub_addr;
-  p_qhd->hub_port                = usbh_devices[dev_addr].hub_port;
+  p_qhd->hub_address             = _usbh_devices[dev_addr].hub_addr;
+  p_qhd->hub_port                = _usbh_devices[dev_addr].hub_port;
   p_qhd->mult                    = 1; // TODO not use high bandwidth/park mode yet
 
   //------------- HCD Management Data -------------//
diff --git a/src/host/usbh.c b/src/host/usbh.c
index 7cb257a8..e96f5f66 100644
--- a/src/host/usbh.c
+++ b/src/host/usbh.c
@@ -118,7 +118,7 @@ enum { USBH_CLASS_DRIVER_COUNT = sizeof(usbh_class_drivers) / sizeof(host_class_
 //--------------------------------------------------------------------+
 // INTERNAL OBJECT & FUNCTION DECLARATION
 //--------------------------------------------------------------------+
-CFG_TUSB_MEM_SECTION usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1]; // including zero-address
+CFG_TUSB_MEM_SECTION usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1]; // including zero-address
 
 OSAL_TASK_DEF(_usbh_task_def, "usbh", usbh_task, CFG_TUH_TASK_PRIO, CFG_TUH_TASK_STACK_SZ);
 
@@ -127,7 +127,7 @@ OSAL_TASK_DEF(_usbh_task_def, "usbh", usbh_task, CFG_TUH_TASK_PRIO, CFG_TUH_TASK
 OSAL_QUEUE_DEF(OPT_MODE_HOST, _usbh_qdef, CFG_TUH_TASK_QUEUE_SZ, hcd_event_t);
 static osal_queue_t _usbh_q;
 
-CFG_TUSB_MEM_SECTION ATTR_ALIGNED(4) STATIC_VAR uint8_t enum_data_buffer[CFG_TUSB_HOST_ENUM_BUFFER_SIZE];
+CFG_TUSB_MEM_SECTION ATTR_ALIGNED(4) static uint8_t _usbh_ctrl_buf[CFG_TUSB_HOST_ENUM_BUFFER_SIZE];
 
 //------------- Reporter Task Data -------------//
 
@@ -141,12 +141,12 @@ static inline uint8_t get_configure_number_for_device(tusb_desc_device_t* dev_de
 tusb_device_state_t tuh_device_get_state (uint8_t const dev_addr)
 {
   TU_ASSERT( dev_addr <= CFG_TUSB_HOST_DEVICE_MAX, TUSB_DEVICE_STATE_INVALID_PARAMETER);
-  return (tusb_device_state_t) usbh_devices[dev_addr].state;
+  return (tusb_device_state_t) _usbh_devices[dev_addr].state;
 }
 
 uint32_t tuh_device_get_mounted_class_flag(uint8_t dev_addr)
 {
-  return tuh_device_is_configured(dev_addr) ? usbh_devices[dev_addr].flag_supported_class : 0;
+  return tuh_device_is_configured(dev_addr) ? _usbh_devices[dev_addr].flag_supported_class : 0;
 }
 
 //--------------------------------------------------------------------+
@@ -154,7 +154,7 @@ uint32_t tuh_device_get_mounted_class_flag(uint8_t dev_addr)
 //--------------------------------------------------------------------+
 bool usbh_init(void)
 {
-  tu_memclr(usbh_devices, sizeof(usbh_device_info_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
+  tu_memclr(_usbh_devices, sizeof(usbh_device_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
 
   //------------- Enumeration & Reporter Task init -------------//
   _usbh_q = osal_queue_create( &_usbh_qdef );
@@ -165,7 +165,7 @@ bool usbh_init(void)
   //------------- Semaphore, Mutex for Control Pipe -------------//
   for(uint8_t i=0; i<CFG_TUSB_HOST_DEVICE_MAX+1; i++) // including address zero
   {
-    usbh_device_info_t * const p_device = &usbh_devices[i];
+    usbh_device_t * const p_device = &_usbh_devices[i];
 
     p_device->control.sem_hdl = osal_semaphore_create(&p_device->control.sem_def);
     TU_ASSERT(p_device->control.sem_hdl != NULL);
@@ -193,7 +193,7 @@ bool usbh_init(void)
 bool usbh_control_xfer_subtask (uint8_t dev_addr, uint8_t bmRequestType, uint8_t bRequest,
                                        uint16_t wValue, uint16_t wIndex, uint16_t wLength, uint8_t* data)
 {
-  usbh_device_info_t* dev = &usbh_devices[dev_addr];
+  usbh_device_t* dev = &_usbh_devices[dev_addr];
 
   TU_ASSERT(osal_mutex_lock(dev->control.mutex_hdl, OSAL_TIMEOUT_NORMAL));
 
@@ -223,7 +223,7 @@ bool usbh_control_xfer_subtask (uint8_t dev_addr, uint8_t bmRequestType, uint8_t
 
 tusb_error_t usbh_pipe_control_open(uint8_t dev_addr, uint8_t max_packet_size)
 {
-  osal_semaphore_reset( usbh_devices[dev_addr].control.sem_hdl );
+  osal_semaphore_reset( _usbh_devices[dev_addr].control.sem_hdl );
   //osal_mutex_reset( usbh_devices[dev_addr].control.mutex_hdl );
 
   TU_ASSERT_ERR( hcd_pipe_control_open(dev_addr, max_packet_size) );
@@ -263,9 +263,9 @@ void usbh_xfer_isr(pipe_handle_t pipe_hdl, uint8_t class_code, xfer_result_t eve
   uint8_t class_index = std_class_code_to_index(class_code);
   if (TUSB_XFER_CONTROL == pipe_hdl.xfer_type)
   {
-    usbh_devices[ pipe_hdl.dev_addr ].control.pipe_status   = event;
+    _usbh_devices[ pipe_hdl.dev_addr ].control.pipe_status   = event;
 //    usbh_devices[ pipe_hdl.dev_addr ].control.xferred_bytes = xferred_bytes; not yet neccessary
-    osal_semaphore_post( usbh_devices[ pipe_hdl.dev_addr ].control.sem_hdl, true );
+    osal_semaphore_post( _usbh_devices[ pipe_hdl.dev_addr ].control.sem_hdl, true );
   }else if (usbh_class_drivers[class_index].isr)
   {
     usbh_class_drivers[class_index].isr(pipe_hdl, event, xferred_bytes);
@@ -279,7 +279,7 @@ void usbh_hub_port_plugged_isr(uint8_t hub_addr, uint8_t hub_port)
 {
   hcd_event_t event =
   {
-    .rhport = usbh_devices[hub_addr].core_id,
+    .rhport = _usbh_devices[hub_addr].core_id,
     .event_id = HCD_EVENT_DEVICE_PLUG
   };
 
@@ -321,15 +321,15 @@ static void usbh_device_unplugged(uint8_t hostid, uint8_t hub_addr, uint8_t hub_
   //------------- find the all devices (star-network) under port that is unplugged -------------//
   for (uint8_t dev_addr = 0; dev_addr <= CFG_TUSB_HOST_DEVICE_MAX; dev_addr ++)
   {
-    if (usbh_devices[dev_addr].core_id  == hostid   &&
-        (hub_addr == 0 || usbh_devices[dev_addr].hub_addr == hub_addr) && // hub_addr == 0 & hub_port == 0 means roothub
-        (hub_port == 0 || usbh_devices[dev_addr].hub_port == hub_port) &&
-        usbh_devices[dev_addr].state    != TUSB_DEVICE_STATE_UNPLUG)
+    if (_usbh_devices[dev_addr].core_id  == hostid   &&
+        (hub_addr == 0 || _usbh_devices[dev_addr].hub_addr == hub_addr) && // hub_addr == 0 & hub_port == 0 means roothub
+        (hub_port == 0 || _usbh_devices[dev_addr].hub_port == hub_port) &&
+        _usbh_devices[dev_addr].state    != TUSB_DEVICE_STATE_UNPLUG)
     {
       // TODO Hub multiple level
       for (uint8_t class_index = 1; class_index < USBH_CLASS_DRIVER_COUNT; class_index++)
       {
-        if ((usbh_devices[dev_addr].flag_supported_class & BIT_(class_index)) &&
+        if ((_usbh_devices[dev_addr].flag_supported_class & BIT_(class_index)) &&
             usbh_class_drivers[class_index].close)
         {
           usbh_class_drivers[class_index].close(dev_addr);
@@ -339,8 +339,8 @@ static void usbh_device_unplugged(uint8_t hostid, uint8_t hub_addr, uint8_t hub_
       // TODO refractor
       // set to REMOVING to allow HCD to clean up its cached data for this device
       // HCD must set this device's state to TUSB_DEVICE_STATE_UNPLUG when done
-      usbh_devices[dev_addr].state = TUSB_DEVICE_STATE_REMOVING;
-      usbh_devices[dev_addr].flag_supported_class = 0;
+      _usbh_devices[dev_addr].state = TUSB_DEVICE_STATE_REMOVING;
+      _usbh_devices[dev_addr].flag_supported_class = 0;
 
       usbh_pipe_control_close(dev_addr);
 
@@ -349,7 +349,7 @@ static void usbh_device_unplugged(uint8_t hostid, uint8_t hub_addr, uint8_t hub_
     }
   }
 
-  if (is_found) hcd_port_unplug(usbh_devices[0].core_id); // TODO hack
+  if (is_found) hcd_port_unplug(_usbh_devices[0].core_id); // TODO hack
 
 }
 
@@ -370,7 +370,8 @@ void usbh_hcd_rhport_unplugged_isr(uint8_t hostid)
 //--------------------------------------------------------------------+
 // ENUMERATION TASK
 //--------------------------------------------------------------------+
-bool usbh_task_body(void)
+
+bool enum_task(hcd_event_t* event)
 {
   enum {
     POWER_STABLE_DELAY = 500,
@@ -378,21 +379,14 @@ bool usbh_task_body(void)
   };
 
   // for OSAL_NONE local variable won't retain value after blocking service sem_wait/queue_recv
-  static uint8_t new_addr;
   static uint8_t configure_selected = 1; // TODO move
   static uint8_t *p_desc = NULL; // TODO move
 
-  hcd_event_t event;
-  if ( !osal_queue_receive(_usbh_q, &event) ) return false;
+  usbh_device_t* dev0 = &_usbh_devices[0];
 
-  // FIXME remove later
-  if ( !(event.event_id == HCD_EVENT_DEVICE_PLUG || event.event_id == HCD_EVENT_DEVICE_UNPLUG) ) return false;
-
-  usbh_device_info_t* dev0 = &usbh_devices[0];
-
-  dev0->core_id  = event.rhport; // TODO refractor integrate to device_pool
-  dev0->hub_addr = event.plug.hub_addr;
-  dev0->hub_port = event.plug.hub_port;
+  dev0->core_id  = event->rhport; // TODO refractor integrate to device_pool
+  dev0->hub_addr = event->plug.hub_addr;
+  dev0->hub_port = event->plug.hub_port;
   dev0->state    = TUSB_DEVICE_STATE_UNPLUG;
 
   //------------- connected/disconnected directly with roothub -------------//
@@ -425,14 +419,14 @@ bool usbh_task_body(void)
     //------------- Get Port Status -------------//
     TU_VERIFY_HDLR( usbh_control_xfer_subtask( dev0->hub_addr, bm_request_type(TUSB_DIR_IN, TUSB_REQ_TYPE_CLASS, TUSB_REQ_RCPT_OTHER),
                                                HUB_REQUEST_GET_STATUS, 0, dev0->hub_port,
-                                               4, enum_data_buffer )
+                                               4, _usbh_ctrl_buf )
                     , hub_status_pipe_queue( dev0->hub_addr) ); // TODO hub refractor
 
     // Acknowledge Port Connection Change
     hub_port_clear_feature_subtask(dev0->hub_addr, dev0->hub_port, HUB_FEATURE_PORT_CONNECTION_CHANGE);
 
     hub_port_status_response_t * p_port_status;
-    p_port_status = ((hub_port_status_response_t *) enum_data_buffer);
+    p_port_status = ((hub_port_status_response_t *) _usbh_ctrl_buf);
 
     if ( ! p_port_status->status_change.connect_status )   return true; // only handle connection change
 
@@ -464,7 +458,7 @@ bool usbh_task_body(void)
   //------------- Get first 8 bytes of device descriptor to get Control Endpoint Size -------------//
   bool is_ok = usbh_control_xfer_subtask(0, bm_request_type(TUSB_DIR_IN, TUSB_REQ_TYPE_STANDARD, TUSB_REQ_RCPT_DEVICE),
                                          TUSB_REQ_GET_DESCRIPTOR,
-                                         (TUSB_DESC_DEVICE << 8), 0, 8, enum_data_buffer);
+                                         (TUSB_DESC_DEVICE << 8), 0, 8, _usbh_ctrl_buf);
 
   //------------- Reset device again before Set Address -------------//
   if (dev0->hub_addr == 0)
@@ -491,7 +485,7 @@ bool usbh_task_body(void)
   #endif
 
   //------------- Set new address -------------//
-  new_addr = get_new_address();
+  uint8_t const new_addr = get_new_address();
   TU_ASSERT(new_addr <= CFG_TUSB_HOST_DEVICE_MAX); // TODO notify application we reach max devices
 
   TU_ASSERT(usbh_control_xfer_subtask( 0, bm_request_type(TUSB_DIR_OUT, TUSB_REQ_TYPE_STANDARD, TUSB_REQ_RCPT_DEVICE),
@@ -499,32 +493,33 @@ bool usbh_task_body(void)
             0, NULL ));
 
   //------------- update port info & close control pipe of addr0 -------------//
-  usbh_devices[new_addr].core_id  = dev0->core_id;
-  usbh_devices[new_addr].hub_addr = dev0->hub_addr;
-  usbh_devices[new_addr].hub_port = dev0->hub_port;
-  usbh_devices[new_addr].speed    = dev0->speed;
-  usbh_devices[new_addr].state    = TUSB_DEVICE_STATE_ADDRESSED;
+  usbh_device_t* new_dev = &_usbh_devices[new_addr];
+  new_dev->core_id  = dev0->core_id;
+  new_dev->hub_addr = dev0->hub_addr;
+  new_dev->hub_port = dev0->hub_port;
+  new_dev->speed    = dev0->speed;
+  new_dev->state    = TUSB_DEVICE_STATE_ADDRESSED;
 
   usbh_pipe_control_close(0);
   dev0->state = TUSB_DEVICE_STATE_UNPLUG;
 
   // open control pipe for new address
-  TU_ASSERT_ERR ( usbh_pipe_control_open(new_addr, ((tusb_desc_device_t*) enum_data_buffer)->bMaxPacketSize0 ) );
+  TU_ASSERT_ERR ( usbh_pipe_control_open(new_addr, ((tusb_desc_device_t*) _usbh_ctrl_buf)->bMaxPacketSize0 ) );
 
   //------------- Get full device descriptor -------------//
   TU_ASSERT(
       usbh_control_xfer_subtask(new_addr, bm_request_type(TUSB_DIR_IN, TUSB_REQ_TYPE_STANDARD, TUSB_REQ_RCPT_DEVICE),
                                      TUSB_REQ_GET_DESCRIPTOR, (TUSB_DESC_DEVICE << 8), 0,
                                 18,
-                                enum_data_buffer));
+                                _usbh_ctrl_buf));
 
   // update device info  TODO alignment issue
-  usbh_devices[new_addr].vendor_id       = ((tusb_desc_device_t*) enum_data_buffer)->idVendor;
-  usbh_devices[new_addr].product_id      = ((tusb_desc_device_t*) enum_data_buffer)->idProduct;
-  usbh_devices[new_addr].configure_count = ((tusb_desc_device_t*) enum_data_buffer)->bNumConfigurations;
+  new_dev->vendor_id       = ((tusb_desc_device_t*) _usbh_ctrl_buf)->idVendor;
+  new_dev->product_id      = ((tusb_desc_device_t*) _usbh_ctrl_buf)->idProduct;
+  new_dev->configure_count = ((tusb_desc_device_t*) _usbh_ctrl_buf)->bNumConfigurations;
 
-  configure_selected = get_configure_number_for_device((tusb_desc_device_t*) enum_data_buffer);
-  TU_ASSERT(configure_selected <= usbh_devices[new_addr].configure_count); // TODO notify application when invalid configuration
+  configure_selected = get_configure_number_for_device((tusb_desc_device_t*) _usbh_ctrl_buf);
+  TU_ASSERT(configure_selected <= new_dev->configure_count); // TODO notify application when invalid configuration
 
   //------------- Get 9 bytes of configuration descriptor -------------//
   TU_ASSERT(
@@ -532,33 +527,33 @@ bool usbh_task_body(void)
                                 TUSB_REQ_GET_DESCRIPTOR,
                                 (TUSB_DESC_CONFIGURATION << 8) | (configure_selected - 1), 0,
                                 9,
-                                enum_data_buffer));
+                                _usbh_ctrl_buf));
 
-  TU_VERIFY_HDLR( CFG_TUSB_HOST_ENUM_BUFFER_SIZE >= ((tusb_desc_configuration_t*)enum_data_buffer)->wTotalLength,
+  TU_VERIFY_HDLR( CFG_TUSB_HOST_ENUM_BUFFER_SIZE >= ((tusb_desc_configuration_t*)_usbh_ctrl_buf)->wTotalLength,
                   tuh_device_mount_failed_cb(TUSB_ERROR_USBH_MOUNT_CONFIG_DESC_TOO_LONG, NULL) );
 
   //------------- Get full configuration descriptor -------------//
   TU_ASSERT( usbh_control_xfer_subtask( new_addr, bm_request_type(TUSB_DIR_IN, TUSB_REQ_TYPE_STANDARD, TUSB_REQ_RCPT_DEVICE),
                                      TUSB_REQ_GET_DESCRIPTOR, (TUSB_DESC_CONFIGURATION << 8) | (configure_selected - 1), 0,
-                                     CFG_TUSB_HOST_ENUM_BUFFER_SIZE, enum_data_buffer ) );
+                                     CFG_TUSB_HOST_ENUM_BUFFER_SIZE, _usbh_ctrl_buf ) );
 
   // update configuration info
-  usbh_devices[new_addr].interface_count = ((tusb_desc_configuration_t*) enum_data_buffer)->bNumInterfaces;
+  new_dev->interface_count = ((tusb_desc_configuration_t*) _usbh_ctrl_buf)->bNumInterfaces;
 
   //------------- Set Configure -------------//
   TU_ASSERT( usbh_control_xfer_subtask( new_addr, bm_request_type(TUSB_DIR_OUT, TUSB_REQ_TYPE_STANDARD, TUSB_REQ_RCPT_DEVICE),
                                      TUSB_REQ_SET_CONFIGURATION, configure_selected, 0,
                                      0, NULL ));
 
-  usbh_devices[new_addr].state = TUSB_DEVICE_STATE_CONFIGURED;
+  new_dev->state = TUSB_DEVICE_STATE_CONFIGURED;
 
   //------------- TODO Get String Descriptors -------------//
 
   //------------- parse configuration & install drivers -------------//
-  p_desc = enum_data_buffer + sizeof(tusb_desc_configuration_t);
+  p_desc = _usbh_ctrl_buf + sizeof(tusb_desc_configuration_t);
 
   // parse each interfaces
-  while( p_desc < enum_data_buffer + ((tusb_desc_configuration_t*)enum_data_buffer)->wTotalLength )
+  while( p_desc < _usbh_ctrl_buf + ((tusb_desc_configuration_t*)_usbh_ctrl_buf)->wTotalLength )
   {
     // skip until we see interface descriptor
     if ( TUSB_DESC_INTERFACE != p_desc[DESC_OFFSET_TYPE] )
@@ -572,15 +567,16 @@ bool usbh_task_body(void)
       TU_ASSERT( class_index != 0 ); // class_index == 0 means corrupted data, abort enumeration
 
       if (usbh_class_drivers[class_index].open_subtask &&
-          !(class_index == TUSB_CLASS_HUB && usbh_devices[new_addr].hub_addr != 0))
-      { // supported class, TODO Hub disable multiple level
+          !(class_index == TUSB_CLASS_HUB && new_dev->hub_addr != 0))
+      {
+        // supported class, TODO Hub disable multiple level
         static uint16_t length;
         length = 0;
 
         if ( usbh_class_drivers[class_index].open_subtask(new_addr, (tusb_desc_interface_t*) p_desc, &length) )
         {
           TU_ASSERT( length >= sizeof(tusb_desc_interface_t) );
-          usbh_devices[new_addr].flag_supported_class |= BIT_(class_index);
+          new_dev->flag_supported_class |= BIT_(class_index);
           p_desc += length;
         }else  // Interface open failed, for example a subclass is not supported
         {
@@ -598,6 +594,22 @@ bool usbh_task_body(void)
   return true;
 }
 
+bool usbh_task_body(void)
+{
+  while (1)
+  {
+    hcd_event_t event;
+    if ( !osal_queue_receive(_usbh_q, &event) ) return false;
+
+    switch (event.event_id)
+    {
+      case HCD_EVENT_DEVICE_PLUG:
+      case HCD_EVENT_DEVICE_UNPLUG:
+        enum_task(&event);
+      break;
+    }
+  }
+}
 
 /* USB Host task
  * Thread that handles all device events. With an real RTOS, the task must be a forever loop and never return.
@@ -626,7 +638,7 @@ static inline uint8_t get_new_address(void)
   uint8_t addr;
   for (addr=1; addr <= CFG_TUSB_HOST_DEVICE_MAX; addr++)
   {
-    if (usbh_devices[addr].state == TUSB_DEVICE_STATE_UNPLUG)
+    if (_usbh_devices[addr].state == TUSB_DEVICE_STATE_UNPLUG)
       break;
   }
   return addr;
diff --git a/src/host/usbh_hcd.h b/src/host/usbh_hcd.h
index d9ab37f4..b4d9adb2 100644
--- a/src/host/usbh_hcd.h
+++ b/src/host/usbh_hcd.h
@@ -86,9 +86,9 @@ typedef struct {
     osal_mutex_def_t mutex_def;
     osal_mutex_t mutex_hdl;    // used to exclusively occupy control pipe
   } control;
-} usbh_device_info_t;
+} usbh_device_t;
 
-extern usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1]; // including zero-address
+extern usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1]; // including zero-address
 
 //--------------------------------------------------------------------+
 // callback from HCD ISR
diff --git a/tests/lpc18xx_43xx/test/host/ehci/test_ehci_init.c b/tests/lpc18xx_43xx/test/host/ehci/test_ehci_init.c
index 69b7c1dd..c61becd6 100644
--- a/tests/lpc18xx_43xx/test/host/ehci/test_ehci_init.c
+++ b/tests/lpc18xx_43xx/test/host/ehci/test_ehci_init.c
@@ -51,7 +51,7 @@
 #include "mock_osal.h"
 #include "mock_usbh_hcd.h"
 
-usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 static uint8_t hostid;
 
diff --git a/tests/lpc18xx_43xx/test/host/ehci/test_ehci_isr.c b/tests/lpc18xx_43xx/test/host/ehci/test_ehci_isr.c
index 6a6beec3..58b8f900 100644
--- a/tests/lpc18xx_43xx/test/host/ehci/test_ehci_isr.c
+++ b/tests/lpc18xx_43xx/test/host/ehci/test_ehci_isr.c
@@ -50,7 +50,7 @@
 #include "mock_osal.h"
 #include "mock_usbh_hcd.h"
 
-usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 static uint8_t hostid;
 static ehci_registers_t * regs;
diff --git a/tests/lpc18xx_43xx/test/host/ehci/test_ehci_structure.c b/tests/lpc18xx_43xx/test/host/ehci/test_ehci_structure.c
index f35c9050..7eaabcd5 100644
--- a/tests/lpc18xx_43xx/test/host/ehci/test_ehci_structure.c
+++ b/tests/lpc18xx_43xx/test/host/ehci/test_ehci_structure.c
@@ -51,7 +51,7 @@
 #include "mock_osal.h"
 #include "mock_usbh_hcd.h"
 
-usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 //--------------------------------------------------------------------+
 // Setup/Teardown + helper declare
diff --git a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_bulk_open.c b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_bulk_open.c
index 581488d7..52cf4055 100644
--- a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_bulk_open.c
+++ b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_bulk_open.c
@@ -51,7 +51,7 @@
 #include "ehci_controller_fake.h"
 #include "host_helper.h"
 
-usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 static uint8_t const hub_addr = 2;
 static uint8_t const hub_port = 2;
@@ -70,7 +70,7 @@ void setUp(void)
   dev_addr = 1;
   hostid = RANDOM(CONTROLLER_HOST_NUMBER) + TEST_CONTROLLER_HOST_START_INDEX;
 
-  tu_memclr(usbh_devices, sizeof(usbh_device_info_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
+  tu_memclr(_usbh_devices, sizeof(usbh_device_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
   helper_usbh_device_emulate(dev_addr, hub_addr, hub_port, hostid, TUSB_SPEED_HIGH);
 
   async_head =  get_async_head( hostid );
@@ -85,7 +85,7 @@ void verify_open_qhd(ehci_qhd_t *p_qhd, uint8_t endpoint_addr, uint16_t max_pack
   TEST_ASSERT_EQUAL(dev_addr, p_qhd->device_address);
   TEST_ASSERT_FALSE(p_qhd->non_hs_period_inactive_next_xact);
   TEST_ASSERT_EQUAL(endpoint_addr & 0x0F, p_qhd->endpoint_number);
-  TEST_ASSERT_EQUAL(usbh_devices[dev_addr].speed, p_qhd->endpoint_speed);
+  TEST_ASSERT_EQUAL(_usbh_devices[dev_addr].speed, p_qhd->endpoint_speed);
   TEST_ASSERT_EQUAL(max_packet_size, p_qhd->max_package_size);
   TEST_ASSERT_EQUAL(0, p_qhd->nak_count_reload); // TDD NAK Reload disable
 
diff --git a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_bulk_xfer.c b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_bulk_xfer.c
index c4037c59..7d206e88 100644
--- a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_bulk_xfer.c
+++ b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_bulk_xfer.c
@@ -51,7 +51,7 @@
 #include "ehci_controller_fake.h"
 #include "host_helper.h"
 
-usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 static uint8_t hub_addr = 2;
 static uint8_t hub_port = 2;
@@ -91,7 +91,7 @@ void setUp(void)
 {
   ehci_controller_init();
   tu_memclr(xfer_data, sizeof(xfer_data));
-  tu_memclr(usbh_devices, sizeof(usbh_device_info_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
+  tu_memclr(_usbh_devices, sizeof(usbh_device_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
 
   TEST_ASSERT_STATUS( hcd_init() );
 
@@ -146,7 +146,7 @@ void verify_qtd(ehci_qtd_t *p_qtd, uint8_t p_data[], uint16_t length)
 
 void test_bulk_xfer_hs_ping_out(void)
 {
-  usbh_devices[dev_addr].speed    = TUSB_SPEED_HIGH;
+  _usbh_devices[dev_addr].speed    = TUSB_SPEED_HIGH;
 
   pipe_handle_t pipe_hdl = hcd_pipe_open(dev_addr, &desc_ept_bulk_out, TUSB_CLASS_MSC);
   ehci_qhd_t *p_qhd = qhd_get_from_pipe_handle(pipe_hdl);
diff --git a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_control_open.c b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_control_open.c
index 426fed9f..0faae0fe 100644
--- a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_control_open.c
+++ b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_control_open.c
@@ -51,7 +51,7 @@
 #include "ehci_controller_fake.h"
 #include "host_helper.h"
 
-usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 static uint8_t const control_max_packet_size = 64;
 static uint8_t const hub_addr = 2;
@@ -67,7 +67,7 @@ static ehci_qhd_t *p_control_qhd;
 //--------------------------------------------------------------------+
 void setUp(void)
 {
-  tu_memclr(usbh_devices, sizeof(usbh_device_info_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
+  tu_memclr(_usbh_devices, sizeof(usbh_device_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
 
   TEST_ASSERT_STATUS( hcd_init() );
 
@@ -90,7 +90,7 @@ void verify_open_qhd(ehci_qhd_t *p_qhd, uint8_t endpoint_addr, uint16_t max_pack
   TEST_ASSERT_EQUAL(dev_addr, p_qhd->device_address);
   TEST_ASSERT_FALSE(p_qhd->non_hs_period_inactive_next_xact);
   TEST_ASSERT_EQUAL(endpoint_addr & 0x0F, p_qhd->endpoint_number);
-  TEST_ASSERT_EQUAL(usbh_devices[dev_addr].speed, p_qhd->endpoint_speed);
+  TEST_ASSERT_EQUAL(_usbh_devices[dev_addr].speed, p_qhd->endpoint_speed);
   TEST_ASSERT_EQUAL(max_packet_size, p_qhd->max_package_size);
   TEST_ASSERT_EQUAL(0, p_qhd->nak_count_reload); // TDD NAK Reload disable
 
@@ -149,7 +149,7 @@ void test_control_open_qhd_data(void)
 
 void test_control_open_highspeed(void)
 {
-  usbh_devices[dev_addr].speed   = TUSB_SPEED_HIGH;
+  _usbh_devices[dev_addr].speed   = TUSB_SPEED_HIGH;
 
   //------------- Code Under TEST -------------//
   TEST_ASSERT_STATUS( hcd_pipe_control_open(dev_addr, control_max_packet_size) );
@@ -158,7 +158,7 @@ void test_control_open_highspeed(void)
 
 void test_control_open_non_highspeed(void)
 {
-  usbh_devices[dev_addr].speed   = TUSB_SPEED_FULL;
+  _usbh_devices[dev_addr].speed   = TUSB_SPEED_FULL;
 
   //------------- Code Under TEST -------------//
   TEST_ASSERT_STATUS( hcd_pipe_control_open(dev_addr, control_max_packet_size) );
diff --git a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_control_xfer.c b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_control_xfer.c
index 4f8cdb4c..bcea7ac8 100644
--- a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_control_xfer.c
+++ b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_control_xfer.c
@@ -51,7 +51,7 @@
 #include "ehci_controller_fake.h"
 #include "host_helper.h"
 
-usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 static uint8_t const control_max_packet_size = 64;
 static uint8_t const hub_addr = 2;
@@ -74,7 +74,7 @@ void setUp(void)
 {
   ehci_controller_init();
 
-  tu_memclr(usbh_devices, sizeof(usbh_device_info_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
+  tu_memclr(_usbh_devices, sizeof(usbh_device_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
   tu_memclr(xfer_data, sizeof(xfer_data));
 
   TEST_ASSERT_STATUS( hcd_init() );
diff --git a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_interrupt_open.c b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_interrupt_open.c
index b243a468..f48b2c7f 100644
--- a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_interrupt_open.c
+++ b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_interrupt_open.c
@@ -50,7 +50,7 @@
 #include "ehci_controller_fake.h"
 #include "host_helper.h"
 
-usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 static uint8_t const hub_addr = 2;
 static uint8_t const hub_port = 2;
@@ -67,7 +67,7 @@ static pipe_handle_t pipe_hdl;
 //--------------------------------------------------------------------+
 void setUp(void)
 {
-  tu_memclr(usbh_devices, sizeof(usbh_device_info_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
+  tu_memclr(_usbh_devices, sizeof(usbh_device_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
 
   hcd_init();
 
@@ -90,7 +90,7 @@ void verify_open_qhd(ehci_qhd_t *p_qhd, uint8_t endpoint_addr, uint16_t max_pack
   TEST_ASSERT_EQUAL(dev_addr, p_qhd->device_address);
   TEST_ASSERT_FALSE(p_qhd->non_hs_period_inactive_next_xact);
   TEST_ASSERT_EQUAL(endpoint_addr & 0x0F, p_qhd->endpoint_number);
-  TEST_ASSERT_EQUAL(usbh_devices[dev_addr].speed, p_qhd->endpoint_speed);
+  TEST_ASSERT_EQUAL(_usbh_devices[dev_addr].speed, p_qhd->endpoint_speed);
   TEST_ASSERT_EQUAL(max_packet_size, p_qhd->max_package_size);
   TEST_ASSERT_EQUAL(0, p_qhd->nak_count_reload); // TDD NAK Reload disable
 
@@ -272,7 +272,7 @@ void test_open_interrupt_hs_interval_8(void)
 
 void test_open_interrupt_qhd_non_hs(void)
 {
-  usbh_devices[dev_addr].speed = TUSB_SPEED_FULL;
+  _usbh_devices[dev_addr].speed = TUSB_SPEED_FULL;
 
   //------------- Code Under TEST -------------//
   pipe_hdl = hcd_pipe_open(dev_addr, &desc_ept_interrupt_out, TUSB_CLASS_HID);
@@ -294,7 +294,7 @@ void test_open_interrupt_qhd_non_hs_9(void)
   tusb_desc_endpoint_t int_edp_interval = desc_ept_interrupt_out;
   int_edp_interval.bInterval = 32;
 
-  usbh_devices[dev_addr].speed = TUSB_SPEED_FULL;
+  _usbh_devices[dev_addr].speed = TUSB_SPEED_FULL;
 
   //------------- Code Under TEST -------------//
   pipe_hdl = hcd_pipe_open(dev_addr, &int_edp_interval, TUSB_CLASS_HID);
diff --git a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_interrupt_xfer.c b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_interrupt_xfer.c
index bf7ad352..5b90652d 100644
--- a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_interrupt_xfer.c
+++ b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_interrupt_xfer.c
@@ -51,7 +51,7 @@
 #include "ehci_controller_fake.h"
 #include "host_helper.h"
 
-usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 static uint8_t const hub_addr = 2;
 static uint8_t const hub_port = 2;
@@ -91,7 +91,7 @@ void setUp(void)
 {
   ehci_controller_init();
 
-  tu_memclr(usbh_devices, sizeof(usbh_device_info_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
+  tu_memclr(_usbh_devices, sizeof(usbh_device_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
   tu_memclr(xfer_data, sizeof(xfer_data));
 
   TEST_ASSERT_STATUS( hcd_init() );
diff --git a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_isochronous_open.c b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_isochronous_open.c
index 1feff94e..51381381 100644
--- a/tests/lpc18xx_43xx/test/host/ehci/test_pipe_isochronous_open.c
+++ b/tests/lpc18xx_43xx/test/host/ehci/test_pipe_isochronous_open.c
@@ -50,7 +50,7 @@
 #include "ehci_controller_fake.h"
 #include "host_helper.h"
 
-usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 static uint8_t const hub_addr = 2;
 static uint8_t const hub_port = 2;
@@ -63,7 +63,7 @@ static ehci_qhd_t *period_head_arr;
 //--------------------------------------------------------------------+
 void setUp(void)
 {
-  tu_memclr(usbh_devices, sizeof(usbh_device_info_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
+  tu_memclr(_usbh_devices, sizeof(usbh_device_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
 
   hcd_init();
 
diff --git a/tests/lpc18xx_43xx/test/host/host_helper.h b/tests/lpc18xx_43xx/test/host/host_helper.h
index b8095b9a..13996d1c 100644
--- a/tests/lpc18xx_43xx/test/host/host_helper.h
+++ b/tests/lpc18xx_43xx/test/host/host_helper.h
@@ -69,11 +69,11 @@ static inline void helper_usbh_init_expect(void)
 
 static inline void helper_usbh_device_emulate(uint8_t dev_addr, uint8_t hub_addr, uint8_t hub_port, uint8_t hostid, tusb_speed_t speed)
 {
-  usbh_devices[dev_addr].core_id  = hostid;
-  usbh_devices[dev_addr].hub_addr = hub_addr;
-  usbh_devices[dev_addr].hub_port = hub_port;
-  usbh_devices[dev_addr].speed    = speed;
-  usbh_devices[dev_addr].state    = dev_addr ? TUSB_DEVICE_STATE_CONFIGURED : TUSB_DEVICE_STATE_UNPLUG;
+  _usbh_devices[dev_addr].core_id  = hostid;
+  _usbh_devices[dev_addr].hub_addr = hub_addr;
+  _usbh_devices[dev_addr].hub_port = hub_port;
+  _usbh_devices[dev_addr].speed    = speed;
+  _usbh_devices[dev_addr].state    = dev_addr ? TUSB_DEVICE_STATE_CONFIGURED : TUSB_DEVICE_STATE_UNPLUG;
 }
 
 
diff --git a/tests/lpc18xx_43xx/test/host/usbh/test_enum_task.c b/tests/lpc18xx_43xx/test/host/usbh/test_enum_task.c
index eba3fbcc..5c11c301 100644
--- a/tests/lpc18xx_43xx/test/host/usbh/test_enum_task.c
+++ b/tests/lpc18xx_43xx/test/host/usbh/test_enum_task.c
@@ -51,7 +51,7 @@
 #include "mock_cdc_host.h"
 #include "mock_msc_host.h"
 
-extern usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+extern usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 extern uint8_t enum_data_buffer[CFG_TUSB_HOST_ENUM_BUFFER_SIZE];
 
 usbh_enumerate_t const enum_connect = {
@@ -73,7 +73,7 @@ enum {
 
 void setUp(void)
 {
-  tu_memclr(usbh_devices, sizeof(usbh_device_info_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
+  tu_memclr(_usbh_devices, sizeof(usbh_device_t)*(CFG_TUSB_HOST_DEVICE_MAX+1));
 
   osal_queue_receive_StubWithCallback(queue_recv_stub);
   osal_semaphore_wait_StubWithCallback(semaphore_wait_success_stub);
@@ -89,8 +89,8 @@ void setUp(void)
   osal_task_delay_Expect(RESET_DELAY);
   hcd_port_speed_get_ExpectAndReturn(enum_connect.core_id, device_speed);
 
-  osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
-  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
+  osal_semaphore_reset_Expect( _usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( _usbh_devices[0].control.mutex_hdl );
   hcd_pipe_control_open_ExpectAndReturn(0, 8, TUSB_ERROR_NONE);
 }
 
@@ -222,53 +222,53 @@ void test_addr0_failed_dev_desc(void)
 
   usbh_enumeration_task(NULL);
 
-  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_ADDRESSED, usbh_devices[0].state);
+  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_ADDRESSED, _usbh_devices[0].state);
 
 }
 
 void test_addr0_failed_set_address(void)
 {
   osal_semaphore_wait_StubWithCallback(semaphore_wait_timeout_stub(1));
-  hcd_port_reset_Expect( usbh_devices[0].core_id );
+  hcd_port_reset_Expect( _usbh_devices[0].core_id );
   osal_task_delay_Expect(RESET_DELAY);
 //  tusbh_device_mount_failed_cb_Expect(TUSB_ERROR_USBH_MOUNT_DEVICE_NOT_RESPOND, NULL);
 
   usbh_enumeration_task(NULL);
 
-  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_ADDRESSED, usbh_devices[0].state);
+  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_ADDRESSED, _usbh_devices[0].state);
   TEST_ASSERT_EQUAL_MEMORY(&desc_device, enum_data_buffer, 8);
 }
 
 void test_enum_failed_get_full_dev_desc(void)
 {
   osal_semaphore_wait_StubWithCallback(semaphore_wait_timeout_stub(2));
-  hcd_port_reset_Expect( usbh_devices[0].core_id );
+  hcd_port_reset_Expect( _usbh_devices[0].core_id );
   osal_task_delay_Expect(RESET_DELAY);
   hcd_pipe_control_close_ExpectAndReturn(0, TUSB_ERROR_NONE);
 
-  osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
-  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
+  osal_semaphore_reset_Expect( _usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( _usbh_devices[0].control.mutex_hdl );
   hcd_pipe_control_open_ExpectAndReturn(1, desc_device.bMaxPacketSize0, TUSB_ERROR_NONE);
 //  tusbh_device_mount_failed_cb_Expect(TUSB_ERROR_USBH_MOUNT_DEVICE_NOT_RESPOND, NULL);
 
   usbh_enumeration_task(NULL);
 
-  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_UNPLUG, usbh_devices[0].state);
-  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_ADDRESSED, usbh_devices[1].state);
-  TEST_ASSERT_EQUAL(TUSB_SPEED_FULL, usbh_devices[1].speed);
-  TEST_ASSERT_EQUAL(enum_connect.core_id, usbh_devices[1].core_id);
-  TEST_ASSERT_EQUAL(enum_connect.hub_addr, usbh_devices[1].hub_addr);
-  TEST_ASSERT_EQUAL(enum_connect.hub_port, usbh_devices[1].hub_port);
+  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_UNPLUG, _usbh_devices[0].state);
+  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_ADDRESSED, _usbh_devices[1].state);
+  TEST_ASSERT_EQUAL(TUSB_SPEED_FULL, _usbh_devices[1].speed);
+  TEST_ASSERT_EQUAL(enum_connect.core_id, _usbh_devices[1].core_id);
+  TEST_ASSERT_EQUAL(enum_connect.hub_addr, _usbh_devices[1].hub_addr);
+  TEST_ASSERT_EQUAL(enum_connect.hub_port, _usbh_devices[1].hub_port);
 }
 
 void test_enum_failed_get_9byte_config_desc(void)
 {
   osal_semaphore_wait_StubWithCallback(semaphore_wait_timeout_stub(3));
-  hcd_port_reset_Expect( usbh_devices[0].core_id );
+  hcd_port_reset_Expect( _usbh_devices[0].core_id );
   osal_task_delay_Expect(RESET_DELAY);
   hcd_pipe_control_close_ExpectAndReturn(0, TUSB_ERROR_NONE);
-  osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
-  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
+  osal_semaphore_reset_Expect( _usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( _usbh_devices[0].control.mutex_hdl );
 
   hcd_pipe_control_open_ExpectAndReturn(1, desc_device.bMaxPacketSize0, TUSB_ERROR_NONE);
   tusbh_device_attached_cb_ExpectAndReturn((tusb_desc_device_t*) enum_data_buffer, 1);
@@ -276,19 +276,19 @@ void test_enum_failed_get_9byte_config_desc(void)
 
   usbh_enumeration_task(NULL);
 
-  TEST_ASSERT_EQUAL(desc_device.idVendor, usbh_devices[1].vendor_id);
-  TEST_ASSERT_EQUAL(desc_device.idProduct, usbh_devices[1].product_id);
-  TEST_ASSERT_EQUAL(desc_device.bNumConfigurations, usbh_devices[1].configure_count);
+  TEST_ASSERT_EQUAL(desc_device.idVendor, _usbh_devices[1].vendor_id);
+  TEST_ASSERT_EQUAL(desc_device.idProduct, _usbh_devices[1].product_id);
+  TEST_ASSERT_EQUAL(desc_device.bNumConfigurations, _usbh_devices[1].configure_count);
 }
 
 void test_enum_failed_get_full_config_desc(void)
 {
   osal_semaphore_wait_StubWithCallback(semaphore_wait_timeout_stub(4));
-  hcd_port_reset_Expect( usbh_devices[0].core_id );
+  hcd_port_reset_Expect( _usbh_devices[0].core_id );
   osal_task_delay_Expect(RESET_DELAY);
   hcd_pipe_control_close_ExpectAndReturn(0, TUSB_ERROR_NONE);
-  osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
-  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
+  osal_semaphore_reset_Expect( _usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( _usbh_devices[0].control.mutex_hdl );
   hcd_pipe_control_open_ExpectAndReturn(1, desc_device.bMaxPacketSize0, TUSB_ERROR_NONE);
   tusbh_device_attached_cb_ExpectAndReturn((tusb_desc_device_t*) enum_data_buffer, 1);
 //  tusbh_device_mount_failed_cb_Expect(TUSB_ERROR_USBH_MOUNT_DEVICE_NOT_RESPOND, NULL);
@@ -299,11 +299,11 @@ void test_enum_failed_get_full_config_desc(void)
 void test_enum_parse_config_desc(void)
 {
   osal_semaphore_wait_StubWithCallback(semaphore_wait_timeout_stub(5));
-  hcd_port_reset_Expect( usbh_devices[0].core_id );
+  hcd_port_reset_Expect( _usbh_devices[0].core_id );
   osal_task_delay_Expect(RESET_DELAY);
   hcd_pipe_control_close_ExpectAndReturn(0, TUSB_ERROR_NONE);
-  osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
-  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
+  osal_semaphore_reset_Expect( _usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( _usbh_devices[0].control.mutex_hdl );
   hcd_pipe_control_open_ExpectAndReturn(1, desc_device.bMaxPacketSize0, TUSB_ERROR_NONE);
   tusbh_device_attached_cb_ExpectAndReturn((tusb_desc_device_t*) enum_data_buffer, 1);
 
@@ -311,17 +311,17 @@ void test_enum_parse_config_desc(void)
 
   usbh_enumeration_task(NULL);
 
-  TEST_ASSERT_EQUAL(desc_configuration.configuration.bNumInterfaces, usbh_devices[1].interface_count);
+  TEST_ASSERT_EQUAL(desc_configuration.configuration.bNumInterfaces, _usbh_devices[1].interface_count);
 }
 
 void test_enum_set_configure(void)
 {
   osal_semaphore_wait_StubWithCallback(semaphore_wait_timeout_stub(6));
-  hcd_port_reset_Expect( usbh_devices[0].core_id );
+  hcd_port_reset_Expect( _usbh_devices[0].core_id );
   osal_task_delay_Expect(RESET_DELAY);
   hcd_pipe_control_close_ExpectAndReturn(0, TUSB_ERROR_NONE);
-  osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
-  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
+  osal_semaphore_reset_Expect( _usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( _usbh_devices[0].control.mutex_hdl );
   hcd_pipe_control_open_ExpectAndReturn(1, desc_device.bMaxPacketSize0, TUSB_ERROR_NONE);
   tusbh_device_attached_cb_ExpectAndReturn((tusb_desc_device_t*) enum_data_buffer, 1);
 
@@ -335,5 +335,5 @@ void test_enum_set_configure(void)
   usbh_enumeration_task(NULL);
 
   TEST_ASSERT_EQUAL( BIT_(TUSB_CLASS_HID) | BIT_(TUSB_CLASS_MSC) | BIT_(TUSB_CLASS_CDC),
-                    usbh_devices[1].flag_supported_class); // TODO change later
+                    _usbh_devices[1].flag_supported_class); // TODO change later
 }
diff --git a/tests/lpc18xx_43xx/test/host/usbh/test_usbh.c b/tests/lpc18xx_43xx/test/host/usbh/test_usbh.c
index 7b99b013..75da7cfd 100644
--- a/tests/lpc18xx_43xx/test/host/usbh/test_usbh.c
+++ b/tests/lpc18xx_43xx/test/host/usbh/test_usbh.c
@@ -68,7 +68,7 @@ void tearDown(void)
 //--------------------------------------------------------------------+
 void test_usbh_status_get_fail(void)
 {
-  usbh_devices[dev_addr].state = 0;
+  _usbh_devices[dev_addr].state = 0;
 
   TEST_ASSERT_EQUAL( TUSB_DEVICE_STATE_INVALID_PARAMETER, tusbh_device_get_state(CFG_TUSB_HOST_DEVICE_MAX+1) );
   TEST_ASSERT_EQUAL( TUSB_DEVICE_STATE_UNPLUG, tusbh_device_get_state(dev_addr) );
@@ -76,7 +76,7 @@ void test_usbh_status_get_fail(void)
 
 void test_usbh_status_get_succeed(void)
 {
-  usbh_devices[dev_addr].state = TUSB_DEVICE_STATE_CONFIGURED;
+  _usbh_devices[dev_addr].state = TUSB_DEVICE_STATE_CONFIGURED;
   TEST_ASSERT_EQUAL( TUSB_DEVICE_STATE_CONFIGURED, tusbh_device_get_state(dev_addr) );
 }
 
@@ -136,7 +136,7 @@ void test_usbh_init_ok(void)
 
   for (uint8_t i=0; i<CFG_TUSB_HOST_DEVICE_MAX+1; i++)
   {
-    TEST_ASSERT_NOT_NULL(usbh_devices[i].control.sem_hdl);
+    TEST_ASSERT_NOT_NULL(_usbh_devices[i].control.sem_hdl);
   }
 }
 
@@ -146,10 +146,10 @@ void test_usbh_hcd_rhport_unplugged_isr_device_not_previously_mounted(void)
 {
   uint8_t dev_addr = 1;
 
-  usbh_devices[dev_addr].state    = TUSB_DEVICE_STATE_UNPLUG;
-  usbh_devices[dev_addr].core_id  = 0;
-  usbh_devices[dev_addr].hub_addr = 0;
-  usbh_devices[dev_addr].hub_port = 0;
+  _usbh_devices[dev_addr].state    = TUSB_DEVICE_STATE_UNPLUG;
+  _usbh_devices[dev_addr].core_id  = 0;
+  _usbh_devices[dev_addr].hub_addr = 0;
+  _usbh_devices[dev_addr].hub_port = 0;
 
   usbh_hcd_rhport_unplugged_isr(0);
 }
@@ -158,11 +158,11 @@ void test_usbh_hcd_rhport_unplugged_isr(void)
 {
   uint8_t dev_addr = 1;
 
-  usbh_devices[dev_addr].state                = TUSB_DEVICE_STATE_CONFIGURED;
-  usbh_devices[dev_addr].core_id              = 0;
-  usbh_devices[dev_addr].hub_addr             = 0;
-  usbh_devices[dev_addr].hub_port             = 0;
-  usbh_devices[dev_addr].flag_supported_class = BIT_(TUSB_CLASS_HID);
+  _usbh_devices[dev_addr].state                = TUSB_DEVICE_STATE_CONFIGURED;
+  _usbh_devices[dev_addr].core_id              = 0;
+  _usbh_devices[dev_addr].hub_addr             = 0;
+  _usbh_devices[dev_addr].hub_port             = 0;
+  _usbh_devices[dev_addr].flag_supported_class = BIT_(TUSB_CLASS_HID);
 
   hidh_close_Expect(dev_addr);
   hcd_pipe_control_close_ExpectAndReturn(dev_addr, TUSB_ERROR_NONE);
@@ -170,18 +170,18 @@ void test_usbh_hcd_rhport_unplugged_isr(void)
   //------------- Code Under Test -------------//
   usbh_hcd_rhport_unplugged_isr(0);
 
-  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_REMOVING, usbh_devices[dev_addr].state);
+  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_REMOVING, _usbh_devices[dev_addr].state);
 }
 
 void test_usbh_device_unplugged_multple_class(void)
 {
   uint8_t dev_addr = 1;
 
-  usbh_devices[dev_addr].state                = TUSB_DEVICE_STATE_CONFIGURED;
-  usbh_devices[dev_addr].core_id              = 0;
-  usbh_devices[dev_addr].hub_addr             = 0;
-  usbh_devices[dev_addr].hub_port             = 0;
-  usbh_devices[dev_addr].flag_supported_class = BIT_(TUSB_CLASS_HID) | BIT_(TUSB_CLASS_MSC) | BIT_(TUSB_CLASS_CDC);
+  _usbh_devices[dev_addr].state                = TUSB_DEVICE_STATE_CONFIGURED;
+  _usbh_devices[dev_addr].core_id              = 0;
+  _usbh_devices[dev_addr].hub_addr             = 0;
+  _usbh_devices[dev_addr].hub_port             = 0;
+  _usbh_devices[dev_addr].flag_supported_class = BIT_(TUSB_CLASS_HID) | BIT_(TUSB_CLASS_MSC) | BIT_(TUSB_CLASS_CDC);
 
   cdch_close_Expect(dev_addr);
   hidh_close_Expect(dev_addr);
@@ -192,7 +192,7 @@ void test_usbh_device_unplugged_multple_class(void)
   //------------- Code Under Test -------------//
   usbh_hcd_rhport_unplugged_isr(0);
 
-  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_REMOVING, usbh_devices[dev_addr].state);
+  TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_REMOVING, _usbh_devices[dev_addr].state);
 
 }
 #endif
@@ -219,7 +219,7 @@ void test_usbh_control_xfer_mutex_failed(void)
   };
 
   osal_mutex_wait_StubWithCallback(mutex_wait_failed_stub);
-  osal_mutex_release_ExpectAndReturn(usbh_devices[dev_addr].control.mutex_hdl, TUSB_ERROR_NONE);
+  osal_mutex_release_ExpectAndReturn(_usbh_devices[dev_addr].control.mutex_hdl, TUSB_ERROR_NONE);
 
   //------------- Code Under Test -------------//
   usbh_control_xfer_subtask(dev_addr, 1, 2, 3, 4, 0, NULL);
@@ -241,7 +241,7 @@ void test_usbh_control_xfer_ok(void)
   hcd_pipe_control_xfer_ExpectAndReturn(dev_addr, &a_request, NULL, TUSB_ERROR_NONE);
   osal_semaphore_wait_StubWithCallback(semaphore_wait_success_stub);
 
-  osal_mutex_release_ExpectAndReturn(usbh_devices[dev_addr].control.mutex_hdl, TUSB_ERROR_NONE);
+  osal_mutex_release_ExpectAndReturn(_usbh_devices[dev_addr].control.mutex_hdl, TUSB_ERROR_NONE);
 
   //------------- Code Under Test -------------//
   usbh_control_xfer_subtask(dev_addr, 1, 2, 3, 4, 0, NULL);
diff --git a/tests/support/ehci_controller_fake.c b/tests/support/ehci_controller_fake.c
index acd40cc0..2c6c919a 100644
--- a/tests/support/ehci_controller_fake.c
+++ b/tests/support/ehci_controller_fake.c
@@ -54,7 +54,7 @@
 LPC_USB0_Type lpc_usb0;
 LPC_USB1_Type lpc_usb1;
 
-extern usbh_device_info_t usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
+extern usbh_device_t _usbh_devices[CFG_TUSB_HOST_DEVICE_MAX+1];
 
 //--------------------------------------------------------------------+
 // IMPLEMENTATION
@@ -67,7 +67,7 @@ void ehci_controller_init(void)
 
 void ehci_controller_control_xfer_proceed(uint8_t dev_addr, uint8_t p_data[])
 {
-  ehci_registers_t* const regs = get_operational_register( usbh_devices[dev_addr].core_id );
+  ehci_registers_t* const regs = get_operational_register( _usbh_devices[dev_addr].core_id );
   ehci_qhd_t * p_qhd = get_control_qhd(dev_addr);
   ehci_qtd_t * p_qtd_setup = get_control_qtds(dev_addr);
   ehci_qtd_t * p_qtd_data  = p_qtd_setup + 1;
@@ -86,7 +86,7 @@ void ehci_controller_control_xfer_proceed(uint8_t dev_addr, uint8_t p_data[])
 
   regs->usb_sts = EHCI_INT_MASK_NXP_ASYNC | EHCI_INT_MASK_NXP_PERIODIC;
 
-  hcd_isr( usbh_devices[dev_addr].core_id );
+  hcd_isr( _usbh_devices[dev_addr].core_id );
 }
 
 void complete_qtd_in_qhd(ehci_qhd_t *p_qhd)