diff --git a/Documentation/NuttxPortingGuide.html b/Documentation/NuttxPortingGuide.html
index 9fda53426cc..20f6778ca8f 100644
--- a/Documentation/NuttxPortingGuide.html
+++ b/Documentation/NuttxPortingGuide.html
@@ -4816,10 +4816,13 @@ build
     Default 4.
   </li>
   <li>
-    <code>CONFIG_CDCSER_VENDORID</code> and <code>CONFIG_CDCSER_VENDORSTR</code>:  The vendor ID code/string.  Default 0x03eb and &quot;NuttX&quot;
+    <code>CONFIG_CDCSER_VENDORID</code> and <code>CONFIG_CDCSER_VENDORSTR</code>:  The vendor ID code/string.  Default 0x0525 and &quot;NuttX,&quot;
+    0x0525 is the Netchip vendor and should not be used in any products.
+    This default VID was selected for compatibility with the Linux CDC ACM default VID.
   </li>
   <li>
-    <code>CONFIG_CDCSER_PRODUCTID</code> and <code>CONFIG_CDCSER_PRODUCTSTR</code>:  The product ID code/string. Default 0x204b and &quot;CDC/ACM Serial&quot;
+    <code>CONFIG_CDCSER_PRODUCTID</code> and <code>CONFIG_CDCSER_PRODUCTSTR</code>:  The product ID code/string. Default 0xa4a7 and &quot;CDC/ACM Serial&quot;
+    0xa4a7 was selected for compatibility with the Linux CDC ACM default PID.
   </li>
   <li>
     <code>CONFIG_CDCSER_RXBUFSIZE</code> and <code>CONFIG_CDCSER_TXBUFSIZE</code>:  Size of the serial receive/transmit buffers.  Default 256.
diff --git a/configs/README.txt b/configs/README.txt
index 8958ee874af..0ea753b6a8f 100644
--- a/configs/README.txt
+++ b/configs/README.txt
@@ -982,9 +982,14 @@ defconfig -- This is a configuration file similar to the Linux
 		  CONFIG_CDCSER_NWRREQS includes write requests used for both the
 		  interrupt and bulk IN endpoints.  Default 4.
 		CONFIG_CDCSER_VENDORID and CONFIG_CDCSER_VENDORSTR
-		  The vendor ID code/string.  Default 0x03eb and "NuttX"
+		  The vendor ID code/string.  Default 0x0525 and "NuttX"
+		  0x0525 is the Netchip vendor and should not be used in any
+		  products.  This default VID was selected for compatibility with
+		  the Linux CDC ACM default VID.
 		CONFIG_CDCSER_PRODUCTID and CONFIG_CDCSER_PRODUCTSTR
-		  The product ID code/string. Default 0x204b and "CDC/ACM Serial"
+		  The product ID code/string. Default 0xa4a7 and "CDC/ACM Serial"
+		  0xa4a7 was selected for compatibility with the Linux CDC ACM
+		  default PID.
 		CONFIG_CDCSER_RXBUFSIZE and CONFIG_CDCSER_TXBUFSIZE
 		  Size of the serial receive/transmit buffers. Default 256.
 
diff --git a/configs/stm3210e-eval/usbserial/defconfig b/configs/stm3210e-eval/usbserial/defconfig
index a23ef58f777..228c70b2036 100755
--- a/configs/stm3210e-eval/usbserial/defconfig
+++ b/configs/stm3210e-eval/usbserial/defconfig
@@ -706,9 +706,14 @@ CONFIG_USBSER_TXBUFSIZE=512
 #   The number of write/read requests that can be in flight.
 #   Default 256.
 # CONFIG_CDCSER_VENDORID and CONFIG_CDCSER_VENDORSTR
-#   The vendor ID code/string.  Default 0x03eb and "NuttX"
+#   The vendor ID code/string.  Default 0x0525 and "NuttX"
+#   0x0525 is the Netchip vendor and should not be used in any
+#   products.  This default VID was selected for compatibility with
+#   the Linux CDC ACM default VID.
 # CONFIG_CDCSER_PRODUCTID and CONFIG_CDCSER_PRODUCTSTR
-#   The product ID code/string. Default 0x204b and "CDC/ACM Serial"
+#   The product ID code/string. Default 0xara7 and "CDC/ACM Serial"
+#   0xa4a7 was selected for compatibility with the Linux CDC ACM
+#   default PID.
 # CONFIG_CDCSER_RXBUFSIZE and CONFIG_CDCSER_TXBUFSIZE
 #   Size of the serial receive/transmit buffers. Default 256.
 #
diff --git a/drivers/usbdev/cdc_serial.c b/drivers/usbdev/cdc_serial.c
index bab4e395183..a4b549d27ea 100644
--- a/drivers/usbdev/cdc_serial.c
+++ b/drivers/usbdev/cdc_serial.c
@@ -338,13 +338,16 @@ static const struct usb_devdesc_s g_devdesc =
   CDC_SUBCLASS_NONE,                            /* subclass */
   CDC_PROTO_NONE,                               /* protocol */
   CONFIG_CDCSER_EP0MAXPACKET,                   /* maxpacketsize */
-  { LSBYTE(CONFIG_CDCSER_VENDORID),             /* vendor */
+  {
+    LSBYTE(CONFIG_CDCSER_VENDORID),             /* vendor */
     MSBYTE(CONFIG_CDCSER_VENDORID)
   },
-  { LSBYTE(CONFIG_CDCSER_PRODUCTID),            /* product */
+  {
+    LSBYTE(CONFIG_CDCSER_PRODUCTID),            /* product */
     MSBYTE(CONFIG_CDCSER_PRODUCTID)
   },
-  { LSBYTE(CDCSER_VERSIONNO),                   /* device */
+  {
+    LSBYTE(CDCSER_VERSIONNO),                   /* device */
     MSBYTE(CDCSER_VERSIONNO)
   },
   CDCSER_MANUFACTURERSTRID,                     /* imfgr */
@@ -550,7 +553,10 @@ static const struct usb_qualdesc_s g_qualdesc =
 {
   USB_SIZEOF_QUALDESC,                          /* len */
   USB_DESC_TYPE_DEVICEQUALIFIER,                /* type */
-  {LSBYTE(0x0200), MSBYTE(0x0200) },            /* USB */
+  {                                             /* usb */
+     LSBYTE(0x0200),
+     MSBYTE(0x0200)
+  },
   USB_CLASS_VENDOR_SPEC,                        /* class */
   0,                                            /* subclass */
   0,                                            /* protocol */
@@ -733,6 +739,9 @@ static inline int usbclass_recvpacket(FAR struct usbser_dev_s *priv,
   uint16_t nexthead;
   uint16_t nbytes = 0;
 
+  uvdbg("head=%d tail=%d nrdq=%d reqlen=%d\n",
+        priv->serdev.recv.head, priv->serdev.recv.tail, priv->nrdq, reqlen);
+
   /* Get the next head index. During the time that RX interrupts are disabled, the
    * the serial driver will be extracting data from the circular buffer and modifying
    * recv.tail.  During this time, we should avoid modifying recv.head; Instead we will
diff --git a/include/nuttx/usb/cdc_serial.h b/include/nuttx/usb/cdc_serial.h
index 92ae62b20ee..8a975666a39 100644
--- a/include/nuttx/usb/cdc_serial.h
+++ b/include/nuttx/usb/cdc_serial.h
@@ -84,9 +84,14 @@
  *   CONFIG_CDCSER_NWRREQS includes write requests used for both the
  *   interrupt and bulk IN endpoints.  Default 4.
  * CONFIG_CDCSER_VENDORID and CONFIG_CDCSER_VENDORSTR
- *   The vendor ID code/string.  Default 0x03eb and "NuttX"
+ *   The vendor ID code/string.  Default 0x0525 and "NuttX"
+ *   0x0525 is the Netchip vendor and should not be used in any
+ *   products.  This default VID was selected for compatibility with
+ *   the Linux CDC ACM default VID.
  * CONFIG_CDCSER_PRODUCTID and CONFIG_CDCSER_PRODUCTSTR
- *   The product ID code/string. Default 0x204b and "CDC/ACM Serial"
+ *   The product ID code/string. Default 0xa4a7 and "CDC/ACM Serial"
+ *   0xa4a7 was selected for compatibility with the Linux CDC ACM
+ *   default PID.
  * CONFIG_CDCSER_RXBUFSIZE and CONFIG_CDCSER_TXBUFSIZE
  *   Size of the serial receive/transmit buffers. Default 256.
  */
@@ -171,14 +176,16 @@
 #  define CONFIG_CDCSER_TXBUFSIZE 256
 #endif
 
-/* Vendor and product IDs and strings */
+/* Vendor and product IDs and strings.  The default is the Linux Netchip
+ * CDC ACM VID and PID.
+ */
 
 #ifndef CONFIG_CDCSER_VENDORID
-#  define CONFIG_CDCSER_VENDORID  0x03eb
+#  define CONFIG_CDCSER_VENDORID  0x0525
 #endif
 
 #ifndef CONFIG_CDCSER_PRODUCTID
-#  define CONFIG_CDCSER_PRODUCTID 0x204b
+#  define CONFIG_CDCSER_PRODUCTID 0xa4a7
 #endif
 
 #ifndef CONFIG_CDCSER_VENDORSTR
@@ -186,7 +193,7 @@
 #endif
 
 #ifndef CONFIG_CDCSER_PRODUCTSTR
-#  define CONFIG_CDCSER_PRODUCTSTR "USBdev Serial"
+#  define CONFIG_CDCSER_PRODUCTSTR "CDC ACM Serial"
 #endif
 
 #undef CONFIG_CDCSER_SERIALSTR