Add Pico dashboard

examples/rp2040/pico-rndis-dashboard/CMakeLists.txt

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+cmake_minimum_required(VERSION 3.13)
+include(pico-sdk/pico_sdk_init.cmake)
+
+project(pico_usb_rndis)
+
+# initialize the Pico SDK
+pico_sdk_init()
+
+add_compile_options(-Wall
+        -Wno-format          # int != int32_t as far as the compiler is concerned because gcc has int32_t as long int
+        -Wno-unused-function # we have some for the docs that aren't called
+        -Wno-maybe-uninitialized
+        )
+
+add_compile_definitions(
+	MIP_DEBUG=1 
+	MG_ENABLE_PACKED_FS=1
+	MG_ENABLE_FILE=0
+	MG_ENABLE_MIP=1
+	DISABLE_ROUTING
+	)
+
+if (TARGET tinyusb_device)
+
+add_executable(firmware
+	main.c
+	mongoose.c
+	net.c
+	packed_fs.c
+	usb_descriptors.c
+	/usr/share/pico_sdk/lib/tinyusb/lib/networking/rndis_reports.c
+	)
+
+# Make sure TinyUSB can find tusb_config.h and workaround SDK include paths
+target_include_directories(firmware PUBLIC
+        ${CMAKE_CURRENT_LIST_DIR}
+	/usr/share/pico_sdk/lib/tinyusb/lib/networking
+	)
+
+# enable uart output
+pico_enable_stdio_usb(firmware 0)
+pico_enable_stdio_uart(firmware 1)
+
+else()
+    message(WARNING "not building because TinyUSB submodule is not initialized in the SDK")
+endif()
+
+target_link_libraries(firmware PUBLIC
+	pico_stdlib
+	tinyusb_device
+	tinyusb_board
+	)
+
+# create map/bin/hex file etc.
+pico_add_extra_outputs(firmware)

examples/rp2040/pico-rndis-dashboard/Makefile

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+SDK_VERSION ?= 1.4.0
+SDK_REPO ?= https://github.com/raspberrypi/pico-sdk
+
+FILES_TO_EMBED ?= $(wildcard web_root/*)
+
+example:
+	true
+
+all build: pico-sdk
+	$(CC) ../../../test/pack.c -o pack
+	./pack $(FILES_TO_EMBED) > packed_fs.c
+	test -d build || mkdir build
+	cd build && cmake .. && make
+
+pico-sdk:
+	git clone --depth 1 -b $(SDK_VERSION) $(SDK_REPO) $@
+	cd $@ && git submodule update --init
+
+clean:
+	rm -rf pico-sdk build pack

examples/rp2040/pico-rndis-dashboard/README.md

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+
+# Device Dashboard via RNDIS on an RP2040
+
+Your headless Raspberry Pi Pico-based hardware can also have a device dashboard on a web browser when you connect it to your computer via USB
+
+## Build and run
+
+Clone Mongoose repo, go to this example, and build it:
+
+```sh
+git clone https://github.com/cesanta/mongoose
+cd mongoose/examples/ro2040/pico-rndis-dashboard
+make build
+```
+
+This will generate a firmware file: `build/firmware.uf2`. Reboot your Pico board in bootloader mode, and copy it to the RPI disk.
+
+The device will reboot, register as a USB RNDIS device, and add a network to your computer.
+Run a browser, and open 192.168.3.1, you should see a device dashboard
+
+Note: USB stdio in the Pico-SDK is done in background with TinyUSB and an interrupt to hide it from the user and periodically call tusb_task(). When we use TinyUSB, that code is removed from the compilation list; so this example uses UART stdio (UART 0) to keep things simple and focused on the RNDIS example. If you want to see the console output, connect an USB-to-UART or a low-voltage-TTL-to-RS-232 adapter to GPIO0

examples/rp2040/pico-rndis-dashboard/main.c

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+// Copyright (c) 2022 Cesanta Software Limited
+// All rights reserved
+
+#include "mongoose.h"
+#include "tusb.h"
+#include "pico/stdlib.h"
+
+static struct mip_if *s_ifp;
+
+const uint8_t tud_network_mac_address[6] = {2, 2, 0x84, 0x6A, 0x96, 0};
+
+static void blink_cb(void *arg) {  // Blink periodically
+  gpio_put(PICO_DEFAULT_LED_PIN, !gpio_get_out_level(PICO_DEFAULT_LED_PIN));
+  (void) arg;
+}
+
+bool tud_network_recv_cb(const uint8_t *buf, uint16_t len) {
+  mip_rxcb((void *) buf, len, s_ifp);
+  // MG_INFO(("RECV %hu", len));
+  // mg_hexdump(buf, len);
+  tud_network_recv_renew();
+  return true;
+}
+
+void tud_network_init_cb(void) {
+}
+
+uint16_t tud_network_xmit_cb(uint8_t *dst, void *ref, uint16_t arg) {
+  // MG_INFO(("SEND %hu", arg));
+  memcpy(dst, ref, arg);
+  return arg;
+}
+
+static size_t usb_tx(const void *buf, size_t len, struct mip_if *ifp) {
+  if (!tud_ready()) return 0;
+  while (!tud_network_can_xmit(len)) tud_task();
+  tud_network_xmit((void *) buf, len);
+  (void) ifp;
+  return len;
+}
+
+static bool usb_up(struct mip_if *ifp) {
+  (void) ifp;
+  return tud_inited() && tud_ready() && tud_connected();
+}
+
+void device_dashboard_fn(struct mg_connection *, int, void *, void *);
+
+int main(void) {
+    gpio_init(PICO_DEFAULT_LED_PIN);
+    gpio_set_dir(PICO_DEFAULT_LED_PIN, GPIO_OUT);
+    stdio_init_all();
+
+  struct mg_mgr mgr;        // Initialise Mongoose event manager
+  mg_mgr_init(&mgr);        // and attach it to the MIP interface
+  mg_timer_add(&mgr, 500, MG_TIMER_REPEAT, blink_cb, &mgr);
+
+  struct mip_driver driver = {.tx = usb_tx, .up = usb_up};
+  struct mip_if mif = {.mac = {2, 0, 1, 2, 3, 0x77},
+                       .ip = mg_htonl(MG_U32(192, 168, 3, 1)),
+                       .mask = mg_htonl(MG_U32(255, 255, 255, 0)),
+                       .enable_dhcp_server = true,
+                       .driver = &driver,
+                       .queue.len = 4096};
+  s_ifp = &mif;
+  mip_init(&mgr, &mif);
+  mg_http_listen(&mgr, "tcp://0.0.0.0:80", device_dashboard_fn, &mgr);
+
+  tusb_init();
+
+  for (;;) {
+    mg_mgr_poll(&mgr, 0);
+    tud_task();
+  }
+
+  return 0;
+}

examples/rp2040/pico-rndis-dashboard/mongoose.c

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+../../../mongoose.c

examples/rp2040/pico-rndis-dashboard/mongoose.h

@@ -0,0 +1 @@
+../../../mongoose.h

examples/rp2040/pico-rndis-dashboard/net.c

@@ -0,0 +1 @@
+../../device-dashboard/net.c

examples/rp2040/pico-rndis-dashboard/netif/ethernet.h

@@ -0,0 +1,2 @@
+#pragma once
+#define SIZEOF_ETH_HDR 14

examples/rp2040/pico-rndis-dashboard/tusb_config.h

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+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * 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_CONFIG_H_
+#define _TUSB_CONFIG_H_
+
+#ifdef __cplusplus
+ extern "C" {
+#endif
+
+//--------------------------------------------------------------------
+// COMMON CONFIGURATION
+//--------------------------------------------------------------------
+
+// defined by board.mk
+#ifndef CFG_TUSB_MCU
+  #error CFG_TUSB_MCU must be defined
+#endif
+
+// RHPort number used for device can be defined by board.mk, default to port 0
+#ifndef BOARD_DEVICE_RHPORT_NUM
+  #define BOARD_DEVICE_RHPORT_NUM     0
+#endif
+
+// RHPort max operational speed can defined by board.mk
+// Default to Highspeed for MCU with internal HighSpeed PHY (can be port specific), otherwise FullSpeed
+#ifndef BOARD_DEVICE_RHPORT_SPEED
+  #if (CFG_TUSB_MCU == OPT_MCU_LPC18XX || CFG_TUSB_MCU == OPT_MCU_LPC43XX || CFG_TUSB_MCU == OPT_MCU_MIMXRT10XX || \
+       CFG_TUSB_MCU == OPT_MCU_NUC505  || CFG_TUSB_MCU == OPT_MCU_CXD56 || CFG_TUSB_MCU == OPT_MCU_SAMX7X)
+    #define BOARD_DEVICE_RHPORT_SPEED   OPT_MODE_HIGH_SPEED
+  #else
+    #define BOARD_DEVICE_RHPORT_SPEED   OPT_MODE_FULL_SPEED
+  #endif
+#endif
+
+// Device mode with rhport and speed defined by board.mk
+#if   BOARD_DEVICE_RHPORT_NUM == 0
+  #define CFG_TUSB_RHPORT0_MODE     (OPT_MODE_DEVICE | BOARD_DEVICE_RHPORT_SPEED)
+#elif BOARD_DEVICE_RHPORT_NUM == 1
+  #define CFG_TUSB_RHPORT1_MODE     (OPT_MODE_DEVICE | BOARD_DEVICE_RHPORT_SPEED)
+#else
+  #error "Incorrect RHPort configuration"
+#endif
+
+#ifndef CFG_TUSB_OS
+#define CFG_TUSB_OS               OPT_OS_NONE
+#endif
+
+// CFG_TUSB_DEBUG is defined by compiler in DEBUG build
+// #define CFG_TUSB_DEBUG           0
+
+/* USB DMA on some MCUs can only access a specific SRAM region with restriction on alignment.
+ * Tinyusb use follows macros to declare transferring memory so that they can be put
+ * into those specific section.
+ * e.g
+ * - CFG_TUSB_MEM SECTION : __attribute__ (( section(".usb_ram") ))
+ * - CFG_TUSB_MEM_ALIGN   : __attribute__ ((aligned(4)))
+ */
+#ifndef CFG_TUSB_MEM_SECTION
+#define CFG_TUSB_MEM_SECTION
+#endif
+
+#ifndef CFG_TUSB_MEM_ALIGN
+#define CFG_TUSB_MEM_ALIGN          __attribute__ ((aligned(4)))
+#endif
+
+//--------------------------------------------------------------------
+// DEVICE CONFIGURATION
+//--------------------------------------------------------------------
+
+#ifndef CFG_TUD_ENDPOINT0_SIZE
+#define CFG_TUD_ENDPOINT0_SIZE    64
+#endif
+
+//------------- CLASS -------------//
+#define CFG_TUD_HID               0
+#define CFG_TUD_CDC               0
+#define CFG_TUD_MSC               0
+#define CFG_TUD_MIDI              0
+#define CFG_TUD_VENDOR            0
+#define CFG_TUD_ECM_RNDIS         1
+#define CFG_TUD_NCM           	  0
+
+// HID buffer size Should be sufficient to hold ID (if any) + Data
+#define CFG_TUD_HID_EP_BUFSIZE    16
+
+#ifdef __cplusplus
+ }
+#endif
+
+#endif /* _TUSB_CONFIG_H_ */

examples/rp2040/pico-rndis-dashboard/usb_descriptors.c

@@ -0,0 +1,248 @@
+/* 
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * 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.
+ *
+ */
+
+#include "tusb.h"
+
+/* A combination of interfaces must have a unique product id, since PC will save device driver after the first plug.
+ * Same VID/PID with different interface e.g MSC (first), then CDC (later) will possibly cause system error on PC.
+ *
+ * Auto ProductID layout's Bitmap:
+ *   [MSB]       NET | VENDOR | MIDI | HID | MSC | CDC          [LSB]
+ */
+#define _PID_MAP(itf, n)  ( (CFG_TUD_##itf) << (n) )
+#define USB_PID           (0x4000 | _PID_MAP(CDC, 0) | _PID_MAP(MSC, 1) | _PID_MAP(HID, 2) | \
+                           _PID_MAP(MIDI, 3) | _PID_MAP(VENDOR, 4) | _PID_MAP(ECM_RNDIS, 5) | _PID_MAP(NCM, 5) )
+
+// String Descriptor Index
+enum
+{
+  STRID_LANGID = 0,
+  STRID_MANUFACTURER,
+  STRID_PRODUCT,
+  STRID_SERIAL,
+  STRID_INTERFACE,
+  STRID_MAC
+};
+
+enum
+{
+  ITF_NUM_CDC = 0,
+  ITF_NUM_CDC_DATA,
+  ITF_NUM_TOTAL
+};
+
+enum
+{
+#if CFG_TUD_ECM_RNDIS
+  CONFIG_ID_RNDIS = 0,
+  CONFIG_ID_ECM   = 1,
+#else
+  CONFIG_ID_NCM   = 0,
+#endif
+  CONFIG_ID_COUNT
+};
+
+//--------------------------------------------------------------------+
+// Device Descriptors
+//--------------------------------------------------------------------+
+tusb_desc_device_t const desc_device =
+{
+    .bLength            = sizeof(tusb_desc_device_t),
+    .bDescriptorType    = TUSB_DESC_DEVICE,
+    .bcdUSB             = 0x0200,
+
+    // Use Interface Association Descriptor (IAD) device class
+    .bDeviceClass       = TUSB_CLASS_MISC,
+    .bDeviceSubClass    = MISC_SUBCLASS_COMMON,
+    .bDeviceProtocol    = MISC_PROTOCOL_IAD,
+    
+    .bMaxPacketSize0    = CFG_TUD_ENDPOINT0_SIZE,
+
+    .idVendor           = 0xCafe,
+    .idProduct          = USB_PID,
+    .bcdDevice          = 0x0101,
+
+    .iManufacturer      = STRID_MANUFACTURER,
+    .iProduct           = STRID_PRODUCT,
+    .iSerialNumber      = STRID_SERIAL,
+
+    .bNumConfigurations = CONFIG_ID_COUNT // multiple configurations
+};
+
+// Invoked when received GET DEVICE DESCRIPTOR
+// Application return pointer to descriptor
+uint8_t const * tud_descriptor_device_cb(void)
+{
+  return (uint8_t const *) &desc_device;
+}
+
+//--------------------------------------------------------------------+
+// Configuration Descriptor
+//--------------------------------------------------------------------+
+#define MAIN_CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + TUD_RNDIS_DESC_LEN)
+#define ALT_CONFIG_TOTAL_LEN     (TUD_CONFIG_DESC_LEN + TUD_CDC_ECM_DESC_LEN)
+#define NCM_CONFIG_TOTAL_LEN     (TUD_CONFIG_DESC_LEN + TUD_CDC_NCM_DESC_LEN)
+
+#if CFG_TUSB_MCU == OPT_MCU_LPC175X_6X || CFG_TUSB_MCU == OPT_MCU_LPC177X_8X || CFG_TUSB_MCU == OPT_MCU_LPC40XX
+  // LPC 17xx and 40xx endpoint type (bulk/interrupt/iso) are fixed by its number
+  // 0 control, 1 In, 2 Bulk, 3 Iso, 4 In etc ...
+  #define EPNUM_NET_NOTIF   0x81
+  #define EPNUM_NET_OUT     0x02
+  #define EPNUM_NET_IN      0x82
+
+#elif CFG_TUSB_MCU == OPT_MCU_SAMG  || CFG_TUSB_MCU ==  OPT_MCU_SAMX7X
+  // SAMG & SAME70 don't support a same endpoint number with different direction IN and OUT
+  //    e.g EP1 OUT & EP1 IN cannot exist together
+  #define EPNUM_NET_NOTIF   0x81
+  #define EPNUM_NET_OUT     0x02
+  #define EPNUM_NET_IN      0x83
+
+#else
+  #define EPNUM_NET_NOTIF   0x81
+  #define EPNUM_NET_OUT     0x02
+  #define EPNUM_NET_IN      0x82
+#endif
+
+#if CFG_TUD_ECM_RNDIS
+
+static uint8_t const rndis_configuration[] =
+{
+  // Config number (index+1), interface count, string index, total length, attribute, power in mA
+  TUD_CONFIG_DESCRIPTOR(CONFIG_ID_RNDIS+1, ITF_NUM_TOTAL, 0, MAIN_CONFIG_TOTAL_LEN, 0, 100),
+
+  // Interface number, string index, EP notification address and size, EP data address (out, in) and size.
+  TUD_RNDIS_DESCRIPTOR(ITF_NUM_CDC, STRID_INTERFACE, EPNUM_NET_NOTIF, 8, EPNUM_NET_OUT, EPNUM_NET_IN, CFG_TUD_NET_ENDPOINT_SIZE),
+};
+
+static uint8_t const ecm_configuration[] =
+{
+  // Config number (index+1), interface count, string index, total length, attribute, power in mA
+  TUD_CONFIG_DESCRIPTOR(CONFIG_ID_ECM+1, ITF_NUM_TOTAL, 0, ALT_CONFIG_TOTAL_LEN, 0, 100),
+
+  // Interface number, description string index, MAC address string index, EP notification address and size, EP data address (out, in), and size, max segment size.
+  TUD_CDC_ECM_DESCRIPTOR(ITF_NUM_CDC, STRID_INTERFACE, STRID_MAC, EPNUM_NET_NOTIF, 64, EPNUM_NET_OUT, EPNUM_NET_IN, CFG_TUD_NET_ENDPOINT_SIZE, CFG_TUD_NET_MTU),
+};
+
+#else
+
+static uint8_t const ncm_configuration[] =
+{
+  // Config number (index+1), interface count, string index, total length, attribute, power in mA
+  TUD_CONFIG_DESCRIPTOR(CONFIG_ID_NCM+1, ITF_NUM_TOTAL, 0, NCM_CONFIG_TOTAL_LEN, 0, 100),
+
+  // Interface number, description string index, MAC address string index, EP notification address and size, EP data address (out, in), and size, max segment size.
+  TUD_CDC_NCM_DESCRIPTOR(ITF_NUM_CDC, STRID_INTERFACE, STRID_MAC, EPNUM_NET_NOTIF, 64, EPNUM_NET_OUT, EPNUM_NET_IN, CFG_TUD_NET_ENDPOINT_SIZE, CFG_TUD_NET_MTU),
+};
+
+#endif
+
+// Configuration array: RNDIS and CDC-ECM
+// - Windows only works with RNDIS
+// - MacOS only works with CDC-ECM
+// - Linux will work on both
+static uint8_t const * const configuration_arr[2] =
+{
+#if CFG_TUD_ECM_RNDIS
+  [CONFIG_ID_RNDIS] = rndis_configuration,
+  [CONFIG_ID_ECM  ] = ecm_configuration
+#else
+  [CONFIG_ID_NCM  ] = ncm_configuration
+#endif
+};
+
+// Invoked when received GET CONFIGURATION DESCRIPTOR
+// Application return pointer to descriptor
+// Descriptor contents must exist long enough for transfer to complete
+uint8_t const * tud_descriptor_configuration_cb(uint8_t index)
+{
+  return (index < CONFIG_ID_COUNT) ? configuration_arr[index] : NULL;
+}
+
+//--------------------------------------------------------------------+
+// String Descriptors
+//--------------------------------------------------------------------+
+
+// array of pointer to string descriptors
+static char const* string_desc_arr [] =
+{
+  [STRID_LANGID]       = (const char[]) { 0x09, 0x04 }, // supported language is English (0x0409)
+  [STRID_MANUFACTURER] = "TinyUSB",                     // Manufacturer
+  [STRID_PRODUCT]      = "TinyUSB Device",              // Product
+  [STRID_SERIAL]       = "123456",                      // Serial
+  [STRID_INTERFACE]    = "TinyUSB Network Interface"    // Interface Description
+
+  // STRID_MAC index is handled separately
+};
+
+static uint16_t _desc_str[32];
+
+// Invoked when received GET STRING DESCRIPTOR request
+// Application return pointer to descriptor, whose contents must exist long enough for transfer to complete
+uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid)
+{
+  (void) langid;
+
+  unsigned int chr_count = 0;
+
+  if (STRID_LANGID == index)
+  {
+    memcpy(&_desc_str[1], string_desc_arr[STRID_LANGID], 2);
+    chr_count = 1;
+  }
+  else if (STRID_MAC == index)
+  {
+    // Convert MAC address into UTF-16
+
+    for (unsigned i=0; i<sizeof(tud_network_mac_address); i++)
+    {
+      _desc_str[1+chr_count++] = "0123456789ABCDEF"[(tud_network_mac_address[i] >> 4) & 0xf];
+      _desc_str[1+chr_count++] = "0123456789ABCDEF"[(tud_network_mac_address[i] >> 0) & 0xf];
+    }
+  }
+  else
+  {
+    // Note: the 0xEE index string is a Microsoft OS 1.0 Descriptors.
+    // https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-defined-usb-descriptors
+
+    if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) return NULL;
+
+    const char* str = string_desc_arr[index];
+
+    // Cap at max char
+    chr_count = (uint8_t) strlen(str);
+    if ( chr_count > (TU_ARRAY_SIZE(_desc_str) - 1)) chr_count = TU_ARRAY_SIZE(_desc_str) - 1;
+
+    // Convert ASCII string into UTF-16
+    for (unsigned int i=0; i<chr_count; i++)
+    {
+      _desc_str[1+i] = str[i];
+    }
+  }
+
+  // first byte is length (including header), second byte is string type
+  _desc_str[0] = (uint16_t) ((TUSB_DESC_STRING << 8 ) | (2*chr_count + 2));
+
+  return _desc_str;
+}