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We would like to implement a slim USB host to store/retrieve small files to/from an USB-flash-drive (with Type-C Plug). We would like to implement an embedded (targeted) host according to the On-the-Go and Embedded Host supplement. We do not want to implement any OTG-functionality, which seems in accordance with the supplement. However, 3.1.3 of that supplement requires Standard-A (to clumsy) and/or Micro AB (needs OTG to implement a host) receptacles. From the type-C specification it seems clear that instead a type-C receptacle may be used (from a technical point of view), as long as CC pins/Vbus are handled properly. However I am missing a clear statement that this supersedes the requirements of the OTG/embedded host supplement. Any hint?

To my understanding, signing an adopters agreement might be possible as long as the product meets the USB specification requirements, even without compliance testing. Does anybody understand if even signing the adopters agreement may be dropped, as long as no copyright protected artwork will be used? Or does using USB-C make mandatory to sign an adopters agreement to avoid patent infringement?

We are talking about a relatively small number of systems. Most real life interoperability issues when using USB flash drives, to my understanding, will be due to the file system (only FAT32 intended, seems to be in accordance with the USB specs), not due to the USB implementation. Therefore, to me, reducing overhead for USB certification testing seems justifiable. Any objections?

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Type-C is a connector specification, and a set of means/rules how it can be useful. The Type-C specification has nothing to do with OTG, in fact, there is not a single mention of OTG in the entire document. Type-C doesn't have the ID pin, and therefore none of OTG methods are applicable. Type-C doesn't "superseeds" OTG, it replaces it entirely.

In place of awkward OTG, micro-AB, session control and other baloney which no-one ever used, Type-C offers a simple and clean model of Port Role switch using CC pins. The Type-C connector doesn't enforce the use of SuperSpeed, it is perfectly legal to have only the USB2.0 signal portion implemented.

Regarding the use of copyrighted artwork. You can't just use the USB artwork. To have a right to use it, your product must pass USB-IF rigorous certification process. To get it done, you must join the USB alliance, and therefore execute the adopters agreement, and then run your device through a certified Lab. Unfortunately, there is no mechanism to enforce this process, so many OEMs either put the artwork illegally, or ignore/skip the entire certification process.

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