AN74505 describes how libusb-1.0 can be used to develop USB host application (Cocoa Application) on MAC OS X 10.6/10.7 for Cypress EZ-USB® FX2LP™ products. This includes step-by-step procedure for developing a host application to communicate with FX2LP products. Here, a bulkloop host application is demonstrated using a bulkloop firmware.
Introduction
AN74505 describes a host application built on the MAC OS platform that uses libusb. The host application (Cocoa Application) communicates with the BULK IN and BULK OUT endpoints of FX2LP, using the interfaces provided by the APIs of libusb. This host application implements the transfer only with devices that pass the particular VID/PID(=0x04B4/0x1004) identification. The example device used in this application note is the bulkloop device. The firmware that is attached along with this application note causes a loop back of data inside the device. It also supports vendor commands, demonstrated here by using a simple vendor command. Thus this host application, with the attached bulkloop device, demonstrates the loopback of bulk data, and control transfers using a vendor command.