USB转双串口，核心技术就在于组合设备（USB Composite）的实现，组合设备的实现，其核心技术在于描述符的实现，下面我们先给出描述符：
设备描述符
[C] 纯文本查看 复制代码
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__ALIGN_BEGIN uint8_t USBD_DeviceDesc[USB_SIZ_DEVICE_DESC] __ALIGN_END = {
0x12, /*bLength */
USB_DEVICE_DESCRIPTOR_TYPE, /*bDescriptorType*/
0x00, /*bcdUSB */
0x02,
#ifdef DUAL_COM 0xEF, /*bDeviceClass*/
0x02, /*bDeviceSubClass*/
0x01, /*bDeviceProtocol*/
#else 0x00, /*bDeviceClass*/
0x00, /*bDeviceSubClass*/
0x00, /*bDeviceProtocol*/ #endif USB_OTG_MAX_EP0_SIZE, /*bMaxPacketSize*/
LOBYTE(USBD_VID), /*idVendor*/
HIBYTE(USBD_VID), /*idVendor*/
LOBYTE(USBD_PID), /*idVendor*/
HIBYTE(USBD_PID), /*idVendor*/
0x00, /*bcdDevice rel. 2.00*/
0x02,
USBD_IDX_MFC_STR, /*Index of manufacturer string*/
USBD_IDX_PRODUCT_STR, /*Index of product string*/
USBD_IDX_SERIAL_STR, /*Index of serial number string*/
USBD_CFG_MAX_NUM /*bNumConfigurations*/
} ; /* USB_DeviceDescriptor */
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注意：双串口需要全局定义DUAL_COM宏
配置描述符是重中之重
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__ALIGN_BEGIN uint8_t usbd_cdc_CfgDesc[USB_CDC_CONFIG_DESC_SIZ] __ALIGN_END ={ /*Configuration Descriptor*/
0x09, /* bLength: Configuration Descriptor size */
USB_CONFIGURATION_DESCRIPTOR_TYPE, /* bDescriptorType: Configuration */
USB_CDC_CONFIG_DESC_SIZ, /* wTotalLength:no of returned bytes */
0x00,
#ifdef DUAL_COM 0x04, /* bNumInterfaces: 4 interface */
#else 0x02, /* bNumInterfaces: 2 interface */
#endif 0x01, /* bConfigurationValue: Configuration value */
0x00, /* iConfiguration: Index of string descriptor describing the configuration */
0x60, /* bmAttributes: self powered */
0xFA, /* MaxPower 0 mA */
/*---------------------------------------------------------------------------*/
#ifdef DUAL_COM // IAD
0x08, // bLength: Interface Descriptor size
0x0B, // bDescriptorType: IAD
0x00, // bFirstInterface
0x02, // bInterfaceCount
0x02, // bFunctionClass: CDC
0x02, // bFunctionSubClass
0x01, // bFunctionProtocol
0x02, // iFunction
#endif /*Interface Descriptor */
0x09, /* bLength: Interface Descriptor size */
USB_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType: Interface */
/* Interface descriptor type */
0x00, /* bInterfaceNumber: Number of Interface */
0x00, /* bAlternateSetting: Alternate setting */
0x01, /* bNumEndpoints: One endpoints used */
0x02, /* bInterfaceClass: Communication Interface Class */
0x02, /* bInterfaceSubClass: Abstract Control Model */
0x01, /* bInterfaceProtocol: Common AT commands */
0x00, /* iInterface: */
/*Header Functional Descriptor*/
0x05, /* bLength: Endpoint Descriptor size */
0x24, /* bDescriptorType: CS_INTERFACE */
0x00, /* bDescriptorSubtype: Header Func Desc */
0x10, /* bcdCDC: spec release number */
0x01,
/*Call Management Functional Descriptor*/
0x05, /* bFunctionLength */
0x24, /* bDescriptorType: CS_INTERFACE */
0x01, /* bDescriptorSubtype: Call Management Func Desc */
0x00, /* bmCapabilities: D0+D1 */
0x01, /* bDataInterface: 1 */
/*ACM Functional Descriptor*/
0x04, /* bFunctionLength */
0x24, /* bDescriptorType: CS_INTERFACE */
0x02, /* bDescriptorSubtype: Abstract Control Management desc */
0x02, /* bmCapabilities */
/*Union Functional Descriptor*/
0x05, /* bFunctionLength */
0x24, /* bDescriptorType: CS_INTERFACE */
0x06, /* bDescriptorSubtype: Union func desc */
0x00, /* bMasterInterface: Communication class interface */
0x01, /* bSlaveInterface0: Data Class Interface */
/*Endpoint 2 Descriptor*/
0x07, /* bLength: Endpoint Descriptor size */
USB_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType: Endpoint */
CDC_CMD_EP, /* bEndpointAddress */
0x03, /* bmAttributes: Interrupt */
LOBYTE(CDC_CMD_PACKET_SZE), /* wMaxPacketSize: */
HIBYTE(CDC_CMD_PACKET_SZE),
0xFF, /* bInterval: */
/*---------------------------------------------------------------------------*/
/*Data class interface descriptor*/
0x09, /* bLength: Endpoint Descriptor size */
USB_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType: */
0x01, /* bInterfaceNumber: Number of Interface */
0x00, /* bAlternateSetting: Alternate setting */
0x02, /* bNumEndpoints: Two endpoints used */
0x0A, /* bInterfaceClass: CDC */
0x00, /* bInterfaceSubClass: */
0x00, /* bInterfaceProtocol: */
0x00, /* iInterface: */
/*Endpoint OUT Descriptor*/
0x07, /* bLength: Endpoint Descriptor size */
USB_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType: Endpoint */
CDC_OUT_EP, /* bEndpointAddress */
0x02, /* bmAttributes: Bulk */
LOBYTE(CDC_DATA_MAX_PACKET_SIZE), /* wMaxPacketSize: */
HIBYTE(CDC_DATA_MAX_PACKET_SIZE),
0x00, /* bInterval: ignore for Bulk transfer */
/*Endpoint IN Descriptor*/
0x07, /* bLength: Endpoint Descriptor size */
USB_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType: Endpoint */
CDC_IN_EP, /* bEndpointAddress */
0x02, /* bmAttributes: Bulk */
LOBYTE(CDC_DATA_MAX_PACKET_SIZE), /* wMaxPacketSize: */
HIBYTE(CDC_DATA_MAX_PACKET_SIZE),
0x00, /* bInterval: ignore for Bulk transfer */
#ifdef DUAL_COM // IAD
0x08, // bLength: Interface Descriptor size
0x0B, // bDescriptorType: IAD
0x02, // bFirstInterface
0x02, // bInterfaceCount
0x02, // bFunctionClass: CDC
0x02, // bFunctionSubClass
0x01, // bFunctionProtocol
0x02, // iFunction
/*Interface Descriptor */
0x09, /* bLength: Interface Descriptor size */
USB_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType: Interface */
/* Interface descriptor type */
0x02, /* bInterfaceNumber: Number of Interface */
0x00, /* bAlternateSetting: Alternate setting */
0x01, /* bNumEndpoints: One endpoints used */
0x02, /* bInterfaceClass: Communication Interface Class */
0x02, /* bInterfaceSubClass: Abstract Control Model */
0x01, /* bInterfaceProtocol: Common AT commands */
0x00, /* iInterface: */
/*Header Functional Descriptor*/
0x05, /* bLength: Endpoint Descriptor size */
0x24, /* bDescriptorType: CS_INTERFACE */
0x00, /* bDescriptorSubtype: Header Func Desc */
0x10, /* bcdCDC: spec release number */
0x01,
/*Call Management Functional Descriptor*/
0x05, /* bFunctionLength */
0x24, /* bDescriptorType: CS_INTERFACE */
0x01, /* bDescriptorSubtype: Call Management Func Desc */
0x00, /* bmCapabilities: D0+D1 */
0x01, /* bDataInterface: 1 */
/*ACM Functional Descriptor*/
0x04, /* bFunctionLength */
0x24, /* bDescriptorType: CS_INTERFACE */
0x02, /* bDescriptorSubtype: Abstract Control Management desc */
0x02, /* bmCapabilities */
/*Union Functional Descriptor*/
0x05, /* bFunctionLength */
0x24, /* bDescriptorType: CS_INTERFACE */
0x06, /* bDescriptorSubtype: Union func desc */
0x00, /* bMasterInterface: Communication class interface */
0x01, /* bSlaveInterface0: Data Class Interface */
/*Endpoint 2 Descriptor*/
0x07, /* bLength: Endpoint Descriptor size */
USB_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType: Endpoint */
CDC_CMD_EP, /* bEndpointAddress */
0x03, /* bmAttributes: Interrupt */
LOBYTE(CDC_CMD_PACKET_SZE), /* wMaxPacketSize: */
HIBYTE(CDC_CMD_PACKET_SZE),
0xFF, /* bInterval: */
/*---------------------------------------------------------------------------*/
/*Data class interface descriptor*/
0x09, /* bLength: Endpoint Descriptor size */
USB_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType: */
0x03, /* bInterfaceNumber: Number of Interface */
0x00, /* bAlternateSetting: Alternate setting */
0x02, /* bNumEndpoints: Two endpoints used */
0x0A, /* bInterfaceClass: CDC */
0x00, /* bInterfaceSubClass: */
0x00, /* bInterfaceProtocol: */
0x00, /* iInterface: */
/*Endpoint OUT Descriptor*/
0x07, /* bLength: Endpoint Descriptor size */
USB_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType: Endpoint */
CDC_OUT_EP_EX, /* bEndpointAddress */
0x02, /* bmAttributes: Bulk */
LOBYTE(CDC_DATA_MAX_PACKET_SIZE), /* wMaxPacketSize: */
HIBYTE(CDC_DATA_MAX_PACKET_SIZE),
0x00, /* bInterval: ignore for Bulk transfer */
/*Endpoint IN Descriptor*/
0x07, /* bLength: Endpoint Descriptor size */
USB_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType: Endpoint */
CDC_IN_EP_EX, /* bEndpointAddress */
0x02, /* bmAttributes: Bulk */
LOBYTE(CDC_DATA_MAX_PACKET_SIZE), /* wMaxPacketSize: */
HIBYTE(CDC_DATA_MAX_PACKET_SIZE),
0x00 /* bInterval: ignore for Bulk transfer */
#endif} ; |
这两个搞定，其他就是USB处理的细节问题了，包括端点的初始化，端点地址分配，数据发送接收的处理等，具体处理和实现程序可参考附件的工程源码。
成功安装驱动
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设备管理器里面的信息
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单片机程序源码： <ignore_js_op>
Ginkgo_USB_COM.rar (1.06 MB, 下载次数: 2)
PC端的驱动安装引导程序： <ignore_js_op> two_com.rar (982 Bytes, 下载次数: 2)
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