Cypress Semiconductor’s West Bridge Antioch chip is designed to sit between a media device CPU, a memory storage device, and a USB host device, providing simultaneous transfers between each connection (see the figure). This allows transfers to occur in a controlled fashion so the directory on the storage device does not get corrupted.
The chip is a tiny file server that employs the Media Transfer Protocol (MTP), which already is used on an array of mobile devices. The big difference is that the west bridge runs at High Speed USB speeds up to 480 Mbits/s using Cypress Semiconductor’s Turbo-MTP support. It allows synchronization with a PC while the media device is using data already on the storage device. The CPU and host PC do not access the directories or files on the storage device directly. This permits transfers of metadata and digital rights management (DRM) that aren’t always available with direct file access.