Controllable USB (Universal Serial Bus) master-slave mode exchange method

Abstract

The invention discloses a controllable USB (universal serial bus) master-slave mode interchange method, which comprises the following steps of initializing an EZ-USB-FX3 (Ethernet Z-USB-FX3), electrifying the EZ-USB-FX3, and entering a slave mode; communicating with equipment; connecting the EZ-USB-FX3 externally connected with a power supply, entering a master mode and monitoring whether USB slave equipment is accessed or not in real time; judging whether the equipment is specified equipment; inquiring whether AOA configuration is supported or not; configuring and starting an AOA mode; judging whether the mode is an AOA mode or not; switching the equipment to a slave mode to establish connection and continuing to work normally; and after equipment charging is completed, sending an instruction, switching to a main mode, and continuing normal work. According to the technical scheme, the AOA protocol configuration is written on the EZ-USB-FX3 platform, the mode is changed into the slave mode under the condition that the electric quantity of the Android master equipment is insufficient, and the original slave equipment is changed into the master mode after the master equipment is externally connected with the power supply, so that the normal work of the USB system can be ensured, the function of charging the Android equipment is realized, the transmission interruption is avoided, and the user experience is greatly optimized.

Description

technical field [0001] The invention relates to the technical field of USB, in particular to a controllable USB master-slave mode interchange method. Background technique [0002] In the USB protocol, the device in the master mode assumes the power supply task of the slave device. The vast majority of android devices on the market do not support current input from the Vbus pin while the USB interface is in use in the main mode, that is, they do not support data output while charging inward through the USB interface. Therefore, in some occasions where a passive slave device is to be used, it will be affected by the above situation, resulting in a portable (built-in battery) Android master device having to stop working normally for charging after working in USB master mode for a period of time. [0003] The AOA protocol is a protocol introduced by Google to implement USB communication between Android devices and peripheral devices. The peripheral USB communication device can...

AI Technical Summary

Problems solved by technology

[0007] The present invention mainly solves the technical problem that the original technical solution cannot be applied to master-slave switching between Android devices and other embedded devices, and provides a controllable USB master-slave mode interchange method, which is written on the EZ-USB-FX3 platform AOA protocol configuration, when the power of the Android master device is insufficient, it will be replaced by the slave mode. The original slave device will be replaced by the master mode after the master device is connected to the external power supply, which can not only ensure the normal operation of the USB system, but also realize the charging of the Android device. After the charging of the Android device is completed, the master-slave mode can be re-exchanged in a controllable manner, and continue to work normally, avoiding transmission interruption, and greatly optimizing the user experience

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