Kinetis MicrocontrollersのトピックRe: Which one is better for general purpose USB host application? CDC or PHDC?

Which one is better for general purpose USB host application? CDC or PHDC?

kai_liu — Tue, 04 Jun 2013 02:49:52 GMT

The USB host application I am working on is Android ADB, which has dedicated interface with BulkIN/BulkOUT EPs.

Following instructions from FSL user manual for USB stack, the enumeration process works well. However, the class APIs are quite different. I want to refers some other class implementation as my code base.

Either CDC/PHDC use BulkIN/BulkOUT as main communication EPs, but their implemenations and structures definitions are quite complex.

Since ADB only requires a pair of Bulk EPs to send/receive messages, which one is more closer to my application? CDC or PHDC?

Re: Which one is better for general purpose USB host application? CDC or PHDC?

kai_liu — Wed, 19 Jun 2013 10:10:06 GMT

PHDC is a better reference than CDC.

Re: Which one is better for general purpose USB host application? CDC or PHDC?

Paul_Tian — Thu, 20 Jun 2013 03:09:12 GMT

Hi, Liu Kai

Yes, you are right. PHDC application expects minimum 2 endpoints, and one is bulk In and the other is bulk out. For detail, you can reference USB stack 4.1.1. and file name is usb_host_phdc.c

Hope my reply can help you.

Best Regards

Paul

Re: Which one is better for general purpose USB host application? CDC or PHDC?

kai_liu — Thu, 20 Jun 2013 11:45:50 GMT

Hi, Paul (Zhe Tian),

Thanks for your reply. After reading specification for CDC/PHDC, I have started to migrate my project based upon PHDC implementation. It is painful since FSL structure is complex and takes longer time to read code than my expectation.

I doubted if anyone can add more stacks on basis of FSL USB host, for example, Bluetooth and WiFi dongles.

Allan K Liu