On 2012-04-17, Rocky <robertgush@gmail.com> wrote:
> I've used it - it worked 'out the box', not that it means that it is
> good. However, I think they get grumpy if you use it on a non-
> Microchip processor.
So Microchip apply the same license to their USB stack as they do to their
header files ?
I should have realised. :-) As I said, I've never actually used it, but I
just saw the "royalty free source code" reference on the Microchip USB
Framework page.
Simon.
--
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world
Reply by Don Y●April 17, 20122012-04-17
On 4/17/2012 9:00 AM, Noob wrote:
> Rocky wrote:
>
>> I've used it - it worked 'out the box', not that it means that it
>> is good. However, I think they get grumpy if you use it on a non-
>> Microchip processor.
>
> I was looking for something with a permissive license, such as
> BSD or MIT. I've given up :-(
Then port one of the {Open,Net,Free}BSD stacks!
> The quality of the current proprietary solution is appalling,
> but I guess I'll have to live with it, and our customers will
> have to learn to unplug/replug or even reboot the STB.
>
> Regards.
Reply by Noob●April 17, 20122012-04-17
Rocky wrote:
> I've used it - it worked 'out the box', not that it means that it
> is good. However, I think they get grumpy if you use it on a non-
> Microchip processor.
I was looking for something with a permissive license, such as
BSD or MIT. I've given up :-(
The quality of the current proprietary solution is appalling,
but I guess I'll have to live with it, and our customers will
have to learn to unplug/replug or even reboot the STB.
Regards.
Reply by Rocky●April 17, 20122012-04-17
On Apr 17, 2:57=A0pm, Simon Clubley <clubley@remove_me.eisner.decus.org-
Earth.UFP> wrote:
> On 2012-04-16, Stef <stef...@yahooI-N-V-A-L-I-D.com.invalid> wrote:
>
>
>
> > Whoops, I think missed hte 'host' part somewhere. The Atmel example is
> > device only, sorry.
>
> Microchip do a USB host stack for their OTG devices; I've no idea if it's
> any good however. See:
>
> http://www.microchip.com/stellent/idcplg?IdcService=3DSS_GET_PAGE&nodeI..=
.
>
> Simon.
I've used it - it worked 'out the box', not that it means that it is
good. However, I think they get grumpy if you use it on a non-
Microchip processor.
Reply by Simon Clubley●April 17, 20122012-04-17
On 2012-04-16, Stef <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote:
>
> Whoops, I think missed hte 'host' part somewhere. The Atmel example is
> device only, sorry.
>
Hi Mark,
On 4/16/2012 7:49 AM, Mark Borgerson wrote:
>>> And just when you thought USB 2.0 was good, there are now HDDs comming
>>> out with USB 3.0 interfaces! ;-)
>>
>> I don't think the higher bandwidth of USB 3 brings anything
>> to the table for a PVR product. Can one plug a USB3 enclosure
>> into a USB2 port?
>
> Good question. You can plug a USB-2 thumb drive into a USB-1 port.
> It works, but the OS complains that it could run faster with a
> USB-2 port. I don't know if the same works with USB-2 and USB-3
Yes, you can plug a USB3 device into a USB2 port. Though
the USB3 end of the cable is very different from a "regular"
USB connection.
Reply by Mark Borgerson●April 16, 20122012-04-16
In article <jmgql7$2lg$1@dont-email.me>, root@127.0.0.1 says...
>
> Mark Borgerson wrote:
>
> > Noob wrote:
> >
> >> Mark Borgerson wrote:
> >>
> >>> Noob wrote:
> >>>
> >>>> USB 2.0 "Hi-Speed" mode is 480 Mbit/s. My goal is 30 MB/s (240 Mbit/s)
> >>>> of "useful" bandwidth (i.e. considering actual data transferred only).
> >>>> IIUC, the overhead in the USB protocol is fairly significant.
> >>>
> >>> That seems to be a pretty ambitious target.
> >>
> >> I can live with 20-25 MB/s ;-)
> >>
> >>> Where is all that data going to go (or come from)?
> >>
> >> A recent 3.5" HDD in a USB2 enclosure (nowadays, 3.5" HDDs
> >> sport 64 MB of cache, and can sustain 50 MB/s over SATA)
> >
> > That's fine for SATA. Have you measured the sustained throughput
> > with USB?
>
> "With the current stack, I've measured 18-20 MB/s sustained."
> But this stack was compiled with gcc -O0, with message queues
> re-implemented using interrupt masking (!!) instead of using
> the OS implementation, with bounce buffers used everywhere,
> and every dynamic memory block allocated from an uncached
> memory pool.
>
> > That sounds like a good recipe for disk thrashing. What kind
> > of file system are you planning to use on the HDD? If it's
> > FAT32, how will maintaining the FAT for 3 files being written
> > affect your throughput? If it's a large disk, caching the
> > whole FAT could use up a lot of your RAM.
>
> FAT sucks. We use ext2 with large blocks.
>
> > To what degree is the throughput constrained by the HDD and file
> > system and not the unnecessary copies?
>
> Seriously? Modern HDDs can sustain 100+ MB/s sequential R/W on the
> outer tracks, 50+ MB/s on the inner tracks. Whatever is the bottle
> neck, it's not the HDD.
Even if the user is maintaining a FAT? How does track access time
affect those throughput numbers?
>
> > And just when you thought USB 2.0 was good, there are now HDDs comming
> > out with USB 3.0 interfaces! ;-)
>
> I don't think the higher bandwidth of USB 3 brings anything
> to the table for a PVR product. Can one plug a USB3 enclosure
> into a USB2 port?
Good question. You can plug a USB-2 thumb drive into a USB-1 port.
It works, but the OS complains that it could run faster with a
USB-2 port. I don't know if the same works with USB-2 and USB-3
>
> Regards.
Mark Borgerson
Reply by Stef●April 16, 20122012-04-16
In comp.arch.embedded,
Arlet Ottens <usenet+5@c-scape.nl> wrote:
> On 04/16/2012 01:41 PM, Stef wrote:
>> In comp.arch.embedded,
>> Noob<root@127.0.0.1> wrote:
>>> Paul wrote:
>>>
>>>> Noob wrote:
>>>>
>>>>> Rob Gaddi wrote:
>>>>>
>>>>>> Have you tried pinging your local Renesas FAE? They might have app
>>>>>> notey sorts of things with already working code.
>>>>>
>>>>> Do you think I can contact Renesas for ST gear?
>>>>>
>>>>> The only thing I want to do with the ST support team
>>>>> involves voodoo dolls and large needles.
>>>>
>>>> Well easy mistake to make as SH-4 architecture also sold by Renesas
>>>> (ex Hitachi division). May still be worth looking at their app notes
>>>> anyway.
>>>
>>> A USB stack (even one limited to mass storage) is not what I would
>>> call trivial software. I'm not sure what to expect from app notes.
>>> Is it common for chip makers to provide full software stacks with
>>> their app notes?
>>
>> I don't know if its 'common', but Atmel did supply a working mass storage
>> example for their SAM7S controllers.
>>
>
> If you strip it down to a point where the host only works with a single
> mass storage device, without a hub, and you don't worry about current
> consumption, suspend mode, or isochronous endpoints, it's not that hard
> to make a USB stack. The app notes I've seen are not much more than this.
Whoops, I think missed hte 'host' part somewhere. The Atmel example is
device only, sorry.
--
Stef (remove caps, dashes and .invalid from e-mail address to reply by mail)
A computer without COBOL and Fortran is like a piece of chocolate cake
without ketchup and mustard.
Reply by Arlet Ottens●April 16, 20122012-04-16
On 04/16/2012 01:41 PM, Stef wrote:
> In comp.arch.embedded,
> Noob<root@127.0.0.1> wrote:
>> Paul wrote:
>>
>>> Noob wrote:
>>>
>>>> Rob Gaddi wrote:
>>>>
>>>>> Have you tried pinging your local Renesas FAE? They might have app
>>>>> notey sorts of things with already working code.
>>>>
>>>> Do you think I can contact Renesas for ST gear?
>>>>
>>>> The only thing I want to do with the ST support team
>>>> involves voodoo dolls and large needles.
>>>
>>> Well easy mistake to make as SH-4 architecture also sold by Renesas
>>> (ex Hitachi division). May still be worth looking at their app notes
>>> anyway.
>>
>> A USB stack (even one limited to mass storage) is not what I would
>> call trivial software. I'm not sure what to expect from app notes.
>> Is it common for chip makers to provide full software stacks with
>> their app notes?
>
> I don't know if its 'common', but Atmel did supply a working mass storage
> example for their SAM7S controllers.
>
If you strip it down to a point where the host only works with a single
mass storage device, without a hub, and you don't worry about current
consumption, suspend mode, or isochronous endpoints, it's not that hard
to make a USB stack. The app notes I've seen are not much more than this.
Reply by Stef●April 16, 20122012-04-16
In comp.arch.embedded,
Noob <root@127.0.0.1> wrote:
> Paul wrote:
>
>> Noob wrote:
>>
>>> Rob Gaddi wrote:
>>>
>>>> Have you tried pinging your local Renesas FAE? They might have app
>>>> notey sorts of things with already working code.
>>>
>>> Do you think I can contact Renesas for ST gear?
>>>
>>> The only thing I want to do with the ST support team
>>> involves voodoo dolls and large needles.
>>
>> Well easy mistake to make as SH-4 architecture also sold by Renesas
>> (ex Hitachi division). May still be worth looking at their app notes
>> anyway.
>
> A USB stack (even one limited to mass storage) is not what I would
> call trivial software. I'm not sure what to expect from app notes.
> Is it common for chip makers to provide full software stacks with
> their app notes?
I don't know if its 'common', but Atmel did supply a working mass storage
example for their SAM7S controllers.
--
Stef (remove caps, dashes and .invalid from e-mail address to reply by mail)
The number of licorice gumballs you get out of a gumball machine
increases in direct proportion to how much you hate licorice.