diff --git a/tests/lpc18xx_43xx/test/host/cdc/test_cdc_host.c b/tests/lpc18xx_43xx/test/host/cdc/test_cdc_host.c
index 53e76a70f..cd95f3fcd 100644
--- a/tests/lpc18xx_43xx/test/host/cdc/test_cdc_host.c
+++ b/tests/lpc18xx_43xx/test/host/cdc/test_cdc_host.c
@@ -144,6 +144,17 @@ void test_cdch_open_interface_number_check(void)
 
 }
 
+void test_cdch_open_acm_capacity_check(void)
+{
+  pipe_handle_t dummy_hld = { .dev_addr = 1 };
+  hcd_pipe_open_IgnoreAndReturn(dummy_hld);
+
+  //------------- CUT -------------//
+  TEST_ASSERT_EQUAL( TUSB_ERROR_NONE, cdch_open_subtask(dev_addr, p_comm_interface, &length) );
+
+  TEST_ASSERT_EQUAL_MEMORY(&cdc_config_descriptor.cdc_acm.bmCapabilities, &p_cdc->acm_capability, 1);
+}
+
 
 
 
diff --git a/tinyusb/class/cdc.h b/tinyusb/class/cdc.h
index 14c7c800b..04f412c9a 100644
--- a/tinyusb/class/cdc.h
+++ b/tinyusb/class/cdc.h
@@ -264,17 +264,21 @@ typedef ATTR_PACKED_STRUCT(struct) {
   uint8_t bDataInterface;
 }tusb_cdc_func_call_management_t;
 
+typedef struct {
+  uint8_t support_comm_request                    : 1; ///< Device supports the request combination of Set_Comm_Feature, Clear_Comm_Feature, and Get_Comm_Feature.
+  uint8_t support_line_request                    : 1; ///< Device supports the request combination of Set_Line_Coding, Set_Control_Line_State, Get_Line_Coding, and the notification Serial_State.
+  uint8_t support_send_break                      : 1; ///< Device supports the request Send_Break
+  uint8_t support_notification_network_connection : 1; ///< Device supports the notification Network_Connection.
+  uint8_t : 0;
+}cdc_fun_acm_capability_t;
+
+STATIC_ASSERT(sizeof(cdc_fun_acm_capability_t) == 1, "mostly problem with compiler");
+
 typedef ATTR_PACKED_STRUCT(struct) {
-  uint8_t bLength            ; ///< Size of this descriptor in bytes.
-  uint8_t bDescriptorType    ; ///< Descriptor Type, must be Class-Specific
-  uint8_t bDescriptorSubType ; ///< Descriptor SubType one of above CDC_FUCN_DESC_
-  struct {
-    uint8_t support_comm_request                    : 1; ///< Device supports the request combination of Set_Comm_Feature, Clear_Comm_Feature, and Get_Comm_Feature.
-    uint8_t support_line_request                    : 1; ///< Device supports the request combination of Set_Line_Coding, Set_Control_Line_State, Get_Line_Coding, and the notification Serial_State.
-    uint8_t support_send_break                      : 1; ///< Device supports the request Send_Break
-    uint8_t support_notification_network_connection : 1; ///< Device supports the notification Network_Connection.
-    uint8_t : 0;
-  } bmCapabilities;
+  uint8_t bLength                  ; ///< Size of this descriptor in bytes.
+  uint8_t bDescriptorType          ; ///< Descriptor Type, must be Class-Specific
+  uint8_t bDescriptorSubType       ; ///< Descriptor SubType one of above CDC_FUCN_DESC_
+  cdc_fun_acm_capability_t bmCapabilities ;
 }tusb_cdc_func_abstract_control_management_t;
 
 typedef ATTR_PACKED_STRUCT(struct) {
@@ -314,16 +318,22 @@ typedef ATTR_PACKED_STRUCT(struct) {
   uint8_t bDescriptorType    ; ///< Descriptor Type, must be Class-Specific
   uint8_t bDescriptorSubType ; ///< Descriptor SubType one of above CDC_FUCN_DESC_
   struct {
-    uint32_t interrupted_dialtone   : 1; ///< 0 – Reports only dialtone (does not differentiate between normal and interrupted dialtone). 1 – Reports interrupted dialtone in addition to normal dialtone
-    uint32_t ringback_busy_fastbusy : 1; ///< 0 – Reports only dialing state. 1 – Reports ringback, busy, and fast busy states.
-    uint32_t caller_id              : 1; ///< 0 – Does not report caller ID. 1 – Reports caller ID information.
-    uint32_t incoming_distinctive   : 1; ///< 0 – Reports only incoming ringing. 1 – Reports incoming distinctive ringing patterns.
-    uint32_t dual_tone_multi_freq   : 1; ///< 0 – Cannot report dual tone multi-frequency (DTMF) digits input remotely over the telephone line. 1 – Can report DTMF digits input remotely over the telephone line.
-    uint32_t line_state_change      : 1; ///< 0 – Does not support line state change notification. 1 – Does support line state change notificatio
+    uint32_t interrupted_dialtone   : 1; ///< 0 : Reports only dialtone (does not differentiate between normal and interrupted dialtone). 1 : Reports interrupted dialtone in addition to normal dialtone
+    uint32_t ringback_busy_fastbusy : 1; ///< 0 : Reports only dialing state. 1 : Reports ringback, busy, and fast busy states.
+    uint32_t caller_id              : 1; ///< 0 : Does not report caller ID. 1 : Reports caller ID information.
+    uint32_t incoming_distinctive   : 1; ///< 0 : Reports only incoming ringing. 1 : Reports incoming distinctive ringing patterns.
+    uint32_t dual_tone_multi_freq   : 1; ///< 0 : Cannot report dual tone multi-frequency (DTMF) digits input remotely over the telephone line. 1 : Can report DTMF digits input remotely over the telephone line.
+    uint32_t line_state_change      : 1; ///< 0 : Does not support line state change notification. 1 : Does support line state change notification
     uint32_t : 0;
   } bmCapabilities;
 }tusb_cdc_func_telephone_call_state_reporting_capabilities_t;
 
+static inline uint8_t functional_desc_typeof(uint8_t const * p_desc) ATTR_PURE ATTR_ALWAYS_INLINE;
+static inline uint8_t functional_desc_typeof(uint8_t const * p_desc)
+{
+  return p_desc[2];
+}
+
 
 #ifdef __cplusplus
  }
diff --git a/tinyusb/class/cdc_host.c b/tinyusb/class/cdc_host.c
index f4d82fc6f..81d992c21 100644
--- a/tinyusb/class/cdc_host.c
+++ b/tinyusb/class/cdc_host.c
@@ -89,6 +89,11 @@ tusb_error_t cdch_open_subtask(uint8_t dev_addr, tusb_descriptor_interface_t con
 
   while( TUSB_DESC_TYPE_INTERFACE_CLASS_SPECIFIC == p_desc[DESCRIPTOR_OFFSET_TYPE] )
   { // Communication Functional Descriptors
+    if ( CDC_FUNC_DESC_ABSTRACT_CONTROL_MANAGEMENT == functional_desc_typeof(p_desc) )
+    { // save ACM bmCapabilities
+      p_cdc->acm_capability = ((tusb_cdc_func_abstract_control_management_t const *) p_desc)->bmCapabilities;
+    }
+
     (*p_length) += p_desc[DESCRIPTOR_OFFSET_LENGTH];
     p_desc = descriptor_next(p_desc);
   }
diff --git a/tinyusb/class/cdc_host.h b/tinyusb/class/cdc_host.h
index 12132ca68..a40cea64e 100644
--- a/tinyusb/class/cdc_host.h
+++ b/tinyusb/class/cdc_host.h
@@ -66,6 +66,8 @@
 typedef struct {
   uint8_t interface_number;
   uint8_t interface_protocol;
+  cdc_fun_acm_capability_t acm_capability;
+
   pipe_handle_t pipe_notification, pipe_out, pipe_in;
 
 } cdch_data_t;