USB hardware logic block Divisor

USB Logic block Divisor

 

 

USBN9603

 

 

 

An2131qc:

 

 

USB hub block digoal

 

Note the following three points:

1. It is the difference between the port and the endpoint. A port is an endpoint of a USB device that is used to control the registers on the chip.

2. The difference between the master device and the slave device is that only the master device has the Host Control and hub. For the slave device, the two registers do not exist.

3. Several USB device descriptors are associated. A USB device has a device descriptor, which determines the number of configurations of the device. Each configuration descriptor corresponds to the configuration descriptor; in the configuration descriptor, the number of interfaces in the configuration is defined, and each interface has the corresponding interface descriptor. In the interface descriptor, the number of endpoints of the interface is defined, each endpoint corresponds to an endpoint descriptor, which defines the size and type of the endpoint. The relationship between USB descriptors is one layer. The top layer is the device descriptor. The following is the configuration descriptor, the interface descriptor, And the endpoint descriptor.

4. Why did I get the three descriptors. When getting a descriptor, get the device descriptor first, then get the configuration descriptor. According to the length of the configuration set in the configuration descriptor, read the configuration descriptor, interface descriptor, and Endpoint descriptor once. The device serial number, vendor string, and product string may also be obtained.