青云翻译

In the early system interface, serial port, parallel port, pic interface. Transmission rate is low, the switch complex and inconvenient to use, and other shortcomings such interfaces exist, resulting in a usb interface.

In the early days the system serial port interface in the main, parallel, PIC interface. Since this type of interface transfer rate is low, switching complex, easy operation and does not disadvantage, such as creating a USB interface.

Mainly has the serial port in the early system connection, parallel mouth, PIC connection and so on.Because this kind of connection existence transmission speed is low, the cut is complex, thus the operation use not convenient and so on the shortcomings have produced the USB connection.

In the early days of system interfaces with the serial port, parallel port, PIC interface, and so on. Because there is such an interface transfer rate low, switching between complex and not easy with such shortcomings resulting in USB interface.

In the early days the system serial port interface in the main, parallel, PIC interface. Since this type of interface transfer rate is low, switching complex, easy operation and does not disadvantage, such as creating a USB interface.