diff --git a/src/class/cdc/serial/cp210x.h b/src/class/cdc/serial/cp210x.h
new file mode 100644
index 000000000..b01417092
--- /dev/null
+++ b/src/class/cdc/serial/cp210x.h
@@ -0,0 +1,64 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2023 Ha Thach (thach@tinyusb.org) for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef TUSB_CP210X_H
+#define TUSB_CP210X_H
+
+// Protocol details can be found at AN571: CP210x Virtual COM Port Interface
+// https://www.silabs.com/documents/public/application-notes/AN571.pdf
+
+#define TU_CP210X_VID 0x10C4
+#define TU_CP210X_PID_LIST \
+  0xEA60, 0xEA70
+
+/* Config request codes */
+#define CP210X_IFC_ENABLE      0x00
+#define CP210X_SET_BAUDDIV     0x01
+#define CP210X_GET_BAUDDIV     0x02
+#define CP210X_SET_LINE_CTL    0x03 // Set parity, data bits, stop bits
+#define CP210X_GET_LINE_CTL    0x04
+#define CP210X_SET_BREAK       0x05
+#define CP210X_IMM_CHAR        0x06
+#define CP210X_SET_MHS         0x07 // Set DTR, RTS
+#define CP210X_GET_MDMSTS      0x08 // Get modem status (DTR, RTS, CTS, DSR, RI, DCD)
+#define CP210X_SET_XON         0x09
+#define CP210X_SET_XOFF        0x0A
+#define CP210X_SET_EVENTMASK   0x0B
+#define CP210X_GET_EVENTMASK   0x0C
+#define CP210X_SET_CHAR        0x0D
+#define CP210X_GET_CHARS       0x0E
+#define CP210X_GET_PROPS       0x0F
+#define CP210X_GET_COMM_STATUS 0x10
+#define CP210X_RESET           0x11
+#define CP210X_PURGE           0x12
+#define CP210X_SET_FLOW        0x13
+#define CP210X_GET_FLOW        0x14
+#define CP210X_EMBED_EVENTS    0x15
+#define CP210X_GET_EVENTSTATE  0x16
+#define CP210X_SET_CHARS       0x19
+#define CP210X_GET_BAUDRATE    0x1D
+#define CP210X_SET_BAUDRATE    0x1E
+#define CP210X_VENDOR_SPECIFIC 0xFF // GPIO, Recipient must be Device
+
+#endif //TUSB_CP210X_H