GP32 USB Host mode- How?

[agustig]

I interesting to programing USB from gp32 with host mode. I know this usb hasn't power, but perhaps i can plug external power.

I think a good project is http://users.skynet.be/firefly/gp32/project/gpusbms/ but the sources for this project isn't open.

Can you help me?

thanks

 

[Squidge]

GPUSBMS isn't a host, as the PC connects to it, so the PC is the host.

You can certainly do host communication, but first you must decide over which protocols you wish to do communication - Control, Interrupt, ISO or Bulk. By default, the GP32 bios does all the control transfers and you only have access to the bulk protocol, but this can be changed.

So, need to know a lot more before I can give you some good advice.

In general, if you need to do something like gpusbms or similar, then you need to get pdf "um_s3c2400x_rev1.1.pdf" from samsung, as this describes the USB interface used in the GP32. You should know all about protocols, end points, descriptors, etc before reading this document as it assumes you already know this. If you don't, your going to have a fun time learning them from usb.org

 

[agustig]

Thanks, I'll begin here.

Because, I want to connect a Mass Storage to gp32, for read and write...

 

[Squidge]

Then I'd suggest you read these documents:

USB Common Class Specification
USB Mass Storage Class CBI Transport (Control/Bulk/Interrupt)
USB Mass Storage Class Bulk Only Transport
USB Mass Storage Class Specification Overview
USB Mass Storage Class UFI Command Specification

These can all be found at the USB Implementors forum, and assume you know how USB works (eg. you know what endpoints are, descriptors, control packets, etc).

You may want to read the documents for ATAPI and MMC/SCSI command sets, as USB Mass Storage uses these commands too.

I also find the Linux kernel source code also provides a lot of helpful code to use in such a project (but again, assumes you know USB)

 

[agustig]

Today, I haven't know how USB work.
And the first, search information about how to USB work.

But, Have you got some source for gp32 what it using USB very educational?

Thanks 4 all!!!