JUNE 4--The USB On-The-Go (OTG) Working Group achieved an important milestone at the official USB-IF Compliance Workshop in May by successfully completing interoperability and preliminary compliance tests. This was the first opportunity for the leading USB OTG integrators to meet and perform initial testing of USB OTG dual-role devices against USB OTG electrical and protocol compliance programs.
Features of the USB OTG Supplement, including Host Negotiation and Session Request Protocols, were demonstrated and tested for compliance using OTG dual-role devices from several vendors. Each sequence of the protocol was performed successfully. This testing served to validate the supplement and helped to refine the compliance test methods and associated test equipment.
Additional testing of OTG dual-role devices was created around the USB Mass Storage Class to enable file transfers between devices. Three different manufacturers were able to connect their OTG dual-role devices together and perform a data transfer to demonstrate interoperability. The first device transferred an audio file to the second device, which then transferred that file to the final device in the chain. Then the final device played the audio file through USB speakers. In each case, the dual-role devices were able to successfully act as both the host and as the peripheral.
The products tested at the compliance workshop will be on display at the upcoming USB 2.0 Developer's Conference, June 10-12, and will be demonstrated during the USB OTG breakout sessions. The successful completion of this milestone means that the OTG Working Group is on target to expand the scope of its compliance program at the next plugfest in August. Adopters of USB OTG can feel confident that the technology is well understood and ready for integration.
The USB On-The-Go Working Group is responsible for writing the USB On-The-Go Supplement to the USB 2.0 Specification and promoting the OTG standard. Contributors to the supplement include ACON, Cypress, Ericsson, Hewlett-Packard, InSilicon, Intel, MCCI, Microsoft, Motorola, NEC, Nokia, Onspec, Palm, Philips, Qualcomm, SoftConnex, Texas Instruments and TransDimension.