diff --git a/tests/test/host/ehci/test_ehci_init.c b/tests/test/host/ehci/test_ehci_init.c
index e311c7c7c..09e7e7f1b 100644
--- a/tests/test/host/ehci/test_ehci_init.c
+++ b/tests/test/host/ehci/test_ehci_init.c
@@ -53,7 +53,6 @@
 
 usbh_device_info_t usbh_devices[TUSB_CFG_HOST_DEVICE_MAX+1];
 
-static uint8_t dev_addr;
 static uint8_t hostid;
 
 //--------------------------------------------------------------------+
@@ -64,15 +63,7 @@ void setUp(void)
   ehci_controller_init();
   TEST_ASSERT_EQUAL( TUSB_ERROR_NONE, hcd_init());
 
-  dev_addr = 1;
   hostid = RANDOM(CONTROLLER_HOST_NUMBER) + TEST_CONTROLLER_HOST_START_INDEX;
-  for (uint8_t i=0; i<TUSB_CFG_HOST_DEVICE_MAX+1; i++)
-  {
-    usbh_devices[i].core_id  = hostid;
-    usbh_devices[i].hub_addr = 0;
-    usbh_devices[i].hub_port = 0;
-    usbh_devices[i].speed    = TUSB_SPEED_HIGH;
-  }
 }
 
 void tearDown(void)
diff --git a/tests/test/host/ehci/test_pipe_bulk_open.c b/tests/test/host/ehci/test_pipe_bulk_open.c
index 34d88e0ed..902aabfcc 100644
--- a/tests/test/host/ehci/test_pipe_bulk_open.c
+++ b/tests/test/host/ehci/test_pipe_bulk_open.c
@@ -48,6 +48,7 @@
 #include "mock_usbh_hcd.h"
 #include "ehci.h"
 #include "ehci_controller_fake.h"
+#include "host_helper.h"
 
 usbh_device_info_t usbh_devices[TUSB_CFG_HOST_DEVICE_MAX+1];
 
@@ -63,17 +64,14 @@ static ehci_qhd_t *async_head;
 //--------------------------------------------------------------------+
 void setUp(void)
 {
-  memclr_(usbh_devices, sizeof(usbh_device_info_t)*(TUSB_CFG_HOST_DEVICE_MAX+1));
-
-  hcd_init();
+  TEST_ASSERT_EQUAL( TUSB_ERROR_NONE,
+                     hcd_init() );
 
   dev_addr = 1;
-
   hostid = RANDOM(CONTROLLER_HOST_NUMBER) + TEST_CONTROLLER_HOST_START_INDEX;
-  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    = TUSB_SPEED_HIGH;
+
+  memclr_(usbh_devices, sizeof(usbh_device_info_t)*(TUSB_CFG_HOST_DEVICE_MAX+1));
+  helper_usbh_device_emulate(dev_addr, hub_addr, hub_port, hostid, TUSB_SPEED_HIGH);
 
   async_head =  get_async_head( hostid );
 }
diff --git a/tests/test/host/ehci/test_pipe_bulk_xfer.c b/tests/test/host/ehci/test_pipe_bulk_xfer.c
index 3ab12fb0e..18cca68c5 100644
--- a/tests/test/host/ehci/test_pipe_bulk_xfer.c
+++ b/tests/test/host/ehci/test_pipe_bulk_xfer.c
@@ -48,11 +48,12 @@
 #include "mock_usbh_hcd.h"
 #include "ehci.h"
 #include "ehci_controller_fake.h"
+#include "host_helper.h"
 
 usbh_device_info_t usbh_devices[TUSB_CFG_HOST_DEVICE_MAX+1];
 
-static uint8_t const hub_addr = 2;
-static uint8_t const hub_port = 2;
+static uint8_t hub_addr = 2;
+static uint8_t hub_port = 2;
 static uint8_t dev_addr;
 static uint8_t hostid;
 static uint8_t xfer_data [18000]; // 18K to test buffer pointer list
@@ -88,21 +89,15 @@ tusb_descriptor_endpoint_t const desc_ept_bulk_out =
 void setUp(void)
 {
   ehci_controller_init();
-
-  memclr_(usbh_devices, sizeof(usbh_device_info_t)*(TUSB_CFG_HOST_DEVICE_MAX+1));
   memclr_(xfer_data, sizeof(xfer_data));
+  memclr_(usbh_devices, sizeof(usbh_device_info_t)*(TUSB_CFG_HOST_DEVICE_MAX+1));
 
   TEST_ASSERT_EQUAL( TUSB_ERROR_NONE,
                      hcd_init() );
 
   dev_addr = 1;
-
   hostid = RANDOM(CONTROLLER_HOST_NUMBER) + TEST_CONTROLLER_HOST_START_INDEX;
-
-  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    = TUSB_SPEED_HIGH;
+  helper_usbh_device_emulate(dev_addr, hub_addr, hub_port, hostid, TUSB_SPEED_HIGH);
 
   async_head =  get_async_head( hostid );
 
diff --git a/tests/test/host/ehci/test_pipe_control_open.c b/tests/test/host/ehci/test_pipe_control_open.c
index b07974200..6a933da06 100644
--- a/tests/test/host/ehci/test_pipe_control_open.c
+++ b/tests/test/host/ehci/test_pipe_control_open.c
@@ -48,6 +48,7 @@
 #include "mock_usbh_hcd.h"
 #include "ehci.h"
 #include "ehci_controller_fake.h"
+#include "host_helper.h"
 
 usbh_device_info_t usbh_devices[TUSB_CFG_HOST_DEVICE_MAX+1];
 
@@ -71,18 +72,10 @@ void setUp(void)
                      hcd_init() );
 
   dev_addr = 1;
-
   hostid = RANDOM(CONTROLLER_HOST_NUMBER) + TEST_CONTROLLER_HOST_START_INDEX;
 
-  usbh_devices[0].core_id  = hostid;
-  usbh_devices[0].hub_addr = hub_addr;
-  usbh_devices[0].hub_port = hub_port;
-  usbh_devices[0].speed    = TUSB_SPEED_HIGH;
-
-  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    = TUSB_SPEED_HIGH;
+  helper_usbh_device_emulate(0, hub_addr, hub_port, hostid, TUSB_SPEED_HIGH);
+  helper_usbh_device_emulate(dev_addr, hub_addr, hub_port, hostid, TUSB_SPEED_HIGH);
 
   async_head =  get_async_head( hostid );
   p_control_qhd = &ehci_data.device[dev_addr-1].control.qhd;
diff --git a/tests/test/host/ehci/test_pipe_control_xfer.c b/tests/test/host/ehci/test_pipe_control_xfer.c
index 1d2da41b8..476a5d8ed 100644
--- a/tests/test/host/ehci/test_pipe_control_xfer.c
+++ b/tests/test/host/ehci/test_pipe_control_xfer.c
@@ -48,6 +48,7 @@
 #include "mock_usbh_hcd.h"
 #include "ehci.h"
 #include "ehci_controller_fake.h"
+#include "host_helper.h"
 
 usbh_device_info_t usbh_devices[TUSB_CFG_HOST_DEVICE_MAX+1];
 
@@ -79,18 +80,10 @@ void setUp(void)
                      hcd_init() );
 
   dev_addr = 1;
+  hostid   = RANDOM(CONTROLLER_HOST_NUMBER) + TEST_CONTROLLER_HOST_START_INDEX;
 
-  hostid = RANDOM(CONTROLLER_HOST_NUMBER) + TEST_CONTROLLER_HOST_START_INDEX;
-
-  usbh_devices[0].core_id  = hostid;
-  usbh_devices[0].hub_addr = hub_addr;
-  usbh_devices[0].hub_port = hub_port;
-  usbh_devices[0].speed    = TUSB_SPEED_HIGH;
-
-  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    = TUSB_SPEED_HIGH;
+  helper_usbh_device_emulate(0        , hub_addr, hub_port, hostid, TUSB_SPEED_HIGH);
+  helper_usbh_device_emulate(dev_addr , hub_addr, hub_port, hostid, TUSB_SPEED_HIGH);
 
   async_head =  get_async_head( hostid );
 
diff --git a/tests/test/host/ehci/test_pipe_interrupt_open.c b/tests/test/host/ehci/test_pipe_interrupt_open.c
index 6e596b312..0b84440e0 100644
--- a/tests/test/host/ehci/test_pipe_interrupt_open.c
+++ b/tests/test/host/ehci/test_pipe_interrupt_open.c
@@ -47,6 +47,7 @@
 #include "mock_usbh_hcd.h"
 #include "ehci.h"
 #include "ehci_controller_fake.h"
+#include "host_helper.h"
 
 usbh_device_info_t usbh_devices[TUSB_CFG_HOST_DEVICE_MAX+1];
 
@@ -70,13 +71,9 @@ void setUp(void)
   hcd_init();
 
   dev_addr = 1;
-
   hostid = RANDOM(CONTROLLER_HOST_NUMBER) + TEST_CONTROLLER_HOST_START_INDEX;
 
-  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    = TUSB_SPEED_HIGH;
+  helper_usbh_device_emulate(dev_addr , hub_addr, hub_port, hostid, TUSB_SPEED_HIGH);
 
   period_head_arr = get_period_head( hostid, 1 );
   p_int_qhd = NULL;
diff --git a/tests/test/host/ehci/test_pipe_interrupt_xfer.c b/tests/test/host/ehci/test_pipe_interrupt_xfer.c
index adf6c62d0..aaa1e213d 100644
--- a/tests/test/host/ehci/test_pipe_interrupt_xfer.c
+++ b/tests/test/host/ehci/test_pipe_interrupt_xfer.c
@@ -48,6 +48,7 @@
 #include "mock_usbh_hcd.h"
 #include "ehci.h"
 #include "ehci_controller_fake.h"
+#include "host_helper.h"
 
 usbh_device_info_t usbh_devices[TUSB_CFG_HOST_DEVICE_MAX+1];
 
@@ -96,13 +97,9 @@ void setUp(void)
                      hcd_init() );
 
   dev_addr = 1;
-
   hostid = RANDOM(CONTROLLER_HOST_NUMBER) + TEST_CONTROLLER_HOST_START_INDEX;
 
-  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    = TUSB_SPEED_HIGH;
+  helper_usbh_device_emulate(dev_addr , hub_addr, hub_port, hostid, TUSB_SPEED_HIGH);
 
   period_head_arr = (ehci_qhd_t*) get_period_head( hostid, 1 );
 
diff --git a/tests/test/host/ehci/test_pipe_isochronous_open.c b/tests/test/host/ehci/test_pipe_isochronous_open.c
index 560ad06ce..df3b407fe 100644
--- a/tests/test/host/ehci/test_pipe_isochronous_open.c
+++ b/tests/test/host/ehci/test_pipe_isochronous_open.c
@@ -47,6 +47,7 @@
 #include "mock_usbh_hcd.h"
 #include "ehci.h"
 #include "ehci_controller_fake.h"
+#include "host_helper.h"
 
 usbh_device_info_t usbh_devices[TUSB_CFG_HOST_DEVICE_MAX+1];
 
@@ -66,15 +67,9 @@ void setUp(void)
   hcd_init();
 
   dev_addr = 1;
-
   hostid = RANDOM(CONTROLLER_HOST_NUMBER) + TEST_CONTROLLER_HOST_START_INDEX;
-  for (uint8_t i=0; i<TUSB_CFG_HOST_DEVICE_MAX+1; i++)
-  {
-    usbh_devices[i].core_id  = hostid;
-    usbh_devices[i].hub_addr = hub_addr;
-    usbh_devices[i].hub_port = hub_port;
-    usbh_devices[i].speed    = TUSB_SPEED_HIGH;
-  }
+
+  helper_usbh_device_emulate(dev_addr , hub_addr, hub_port, hostid, TUSB_SPEED_HIGH);
 
   period_head_arr = get_period_head( hostid, 1 );
 }
diff --git a/tests/test/host/hid/test_hidh_mouse.c b/tests/test/host/hid/test_hidh_mouse.c
index 1496e6676..c169a6099 100644
--- a/tests/test/host/hid/test_hidh_mouse.c
+++ b/tests/test/host/hid/test_hidh_mouse.c
@@ -41,6 +41,7 @@
 #include "type_helper.h"
 #include "errors.h"
 #include "common/common.h"
+
 #include "hid_host.h"
 #include "mock_osal.h"
 #include "mock_usbh.h"