USB Mass Storage Device with HPS Stack
Hans Petter Selasky
hselasky at c2i.net
Thu May 1 18:24:04 UTC 2008
On Thursday 01 May 2008, Xiaofan Chen wrote:
> On Thu, May 1, 2008 at 12:30 AM, Hans Petter Selasky <hselasky at c2i.net>
> > Try and find out. I know that many structures can be optimized for
> > minimal memory usage. Currently I reserve space for 128 USB devices and
> > 32 endpoints and interfaces. If you reduce those numbers then you will
> > save a lot of memory.
> I am a bit confused now. So your USB stack now can be used for
> Device side which does not require FreeBSD OS support. Is this
There you got it! My new USB stack is completely symmetric. You use the same
callback API in USB Host mode and USB Device mode!
> I thought your device side stack is like Linux Gadget which runs
> some kind of Linux and then act as an usb function device (slave)
> to a USB host.
Nope, it is fully symmetric.
> I am getting two new USB development boards from Microchip,
> PIC24 16bit and PIC32 32 bit (MIPS based) USB, both with OTG, both
> will not be able to run FreeBSD or Linux or even uClinux due to memory
> constraint. I have the Olimex LPC-P2148 (ARM7 based) as well which
> could not run FreeBSD/Linux either.
> Do you think any of them can run your stack's device side?
With a little work it will not be a problem. You need to support mutexes and a
few other things that are specific to USB.
> What is your test platform for your stack's device side? Does
> it run FreeBSD?
AT91RM9200 (KB9202B from Kwikbyte)
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