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<?xml-stylesheet type="text/xsl" href="https://community.arm.com/utility/feedstylesheets/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:wfw="http://wellformedweb.org/CommentAPI/"><channel><title>Increasing speed in interrupt tranfer</title><link>https://community.arm.com/developer/tools-software/tools/f/keil-forum/27770/increasing-speed-in-interrupt-tranfer</link><description> 
The maximum speed for the interrupt transfer for USB 2.0 full
speed is 64kbytes/s. LPC2148 is used in device side. Is there a
possibility of increasing the interrupt transfer speed by increasing
the packet size. In that case generic device class wont</description><dc:language>en-US</dc:language><generator>Telligent Community 10</generator><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/143031?ContentTypeID=1</link><pubDate>Wed, 02 Nov 2011 05:19:54 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:ddfe42f3-28dd-4a01-ae05-580c71b8c769</guid><dc:creator>Shahida Asharf</dc:creator><description>&lt;p&gt;&lt;p&gt;
Hi All,&lt;br /&gt;
We are planning to buy Bulk based USB Driver. Can please you suggest
me some.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/140089?ContentTypeID=1</link><pubDate>Sun, 30 Oct 2011 21:28:11 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:742e381a-f07a-4859-9239-f67444632fb2</guid><dc:creator>Shahida Asharf</dc:creator><description>&lt;p&gt;&lt;p&gt;
Hi Tsuneo&lt;br /&gt;
Thanks for the reply.For our application even if other devices are
there in the USB bus it should guaranty data correctness and time.
Thats why we chose interrupt transfer instead of bulk transfer. But
we could find that the speed of interrupt transfer is not sufficient
for our application. Any other possible solution? Thanks for helping
me out Tsuneo.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/136639?ContentTypeID=1</link><pubDate>Wed, 26 Oct 2011 09:10:44 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:976a189c-b1cd-4900-8988-b3cea0a8b044</guid><dc:creator>Chinzei Tsuneo</dc:creator><description>&lt;p&gt;&lt;p&gt;
OK, Per. He is hard :-)&lt;/p&gt;

&lt;p&gt;
&lt;i&gt;&amp;gt; The problem in using bulk trnsfer is that application will
be tested in the stress condition loading the PC with many other
applications and it is expected to meet both guarantied data and
time. Thats why the interrupt transfer was chose.&lt;/i&gt;&lt;/p&gt;

&lt;p&gt;
Under stressed condition of PC, any transfer type can&amp;#39;t guarantee
transfer timing. No difference for bulk from interrupt. The interrupt
bandwidth is guaranteed just on the USB wire. If PC device driver or
your application can&amp;#39;t pass transfer requests to the host controller
in time, the guaranteed bandwidth is lost in vain.&lt;/p&gt;

&lt;p&gt;
&lt;i&gt;&amp;gt; If we go for custom driver also the packet size increasing
is not possible?&lt;/i&gt;&lt;/p&gt;

&lt;p&gt;
It can&amp;#39;t.&lt;br /&gt;
USB spec defines wMaxPacketSize of interrupt as up to 64 bytes in
full-speed.&lt;/p&gt;

&lt;p&gt;
If you want to guarantee such a high transfer speed on full-speed,
run it on bulk with a separated host controller (add-on PCI card for
USB), so that the device can occupy full bandwidth. Or, insert a
multi-TT hub between the bulk device and the PC.&lt;/p&gt;

&lt;p&gt;
Multi-TT hubs&lt;br /&gt;
Belkin F5U234V1, F5U237v1&lt;br /&gt;
etc.&lt;/p&gt;

&lt;p&gt;
Tsuneo&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/127182?ContentTypeID=1</link><pubDate>Wed, 26 Oct 2011 07:45:43 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:b9f2eba6-638a-484c-9ebe-55d042701282</guid><dc:creator>Shahida Asharf</dc:creator><description>&lt;p&gt;&lt;p&gt;
Hello Westermark, Thanks for the reply.USB 2.0 full speed is the
only scope. If we go for custom driver also the packet size
increasing is not possible? Thanks in advance.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/119516?ContentTypeID=1</link><pubDate>Wed, 26 Oct 2011 07:41:49 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:a32f7193-808a-4854-ab0a-0f68554ec8fa</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
s/Two/Three/&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/116562?ContentTypeID=1</link><pubDate>Wed, 26 Oct 2011 07:41:26 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:30940261-1cb6-4d0c-b18d-84da4265caf3</guid><dc:creator>Shahida Asharf</dc:creator><description>&lt;p&gt;&lt;p&gt;
Hello Westermark,&lt;br /&gt;
Thanks for the reply. The problem in using bulk trnsfer is that
application will be tested in the stress condition loading the PC
with many other applications and it is expected to meet both
guarantied data and time. Thats why the interrupt transfer was chose.
So your opinion is the maximum packet size cannot be increased from
64bytes for interrupt transfer in any method? Our present scope is
using usb 2.0 full speed only. Your suggession will be very helpful
to me.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/105407?ContentTypeID=1</link><pubDate>Wed, 26 Oct 2011 07:23:48 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:bc10eaba-6b2d-4023-bb66-07d57ea353c1</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
Two things.&lt;/p&gt;

&lt;p&gt;
1) Who would claim your required bandwidth? Just make sure that
you don&amp;#39;t connect through a USB hub and no other device should be
there to steal bandwidth on the cable.&lt;/p&gt;

&lt;p&gt;
2) Firewire allows allocation of way more bandwidth. Yes. Much
more expensive. But you get what you pay for. If you do not want to
take the cost of a bus designed to allow you to allocate x Mbit/s of
dedicated bandwidth, then you will have to settle for what you can
get from the standards you do pay for.&lt;/p&gt;

&lt;p&gt;
3) Or you may look into ethernet together with QoS.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/79701?ContentTypeID=1</link><pubDate>Wed, 26 Oct 2011 07:02:59 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:786e608e-0dff-4e67-b875-39aeec0740ce</guid><dc:creator>Shahida Asharf</dc:creator><description>&lt;p&gt;&lt;p&gt;
Hello Westermark,&lt;/p&gt;

&lt;p&gt;
Thanks alot for your reply. In the bulk transfer guarantied time
delivery is not there. In case the bus is busy there will be delay as
there is no reserved bandwidth. Our application demands both time and
data correctness. In the books and websites the maximum speed
possible for the interrupt transfer was found to be 64 kbytes/sec per
end point. The core used is LPC2148 which gives 5 interrupt IN
endpoints. So maximum speed possible 320kbytes/s. But more speed is
demanded for our application. Currently HID device class driver is
used which supports interrupt transfer.Is there any possibility of
increasing the maximum packet size from 64bytes? I tried increasing
the packet size but the enumeration fails. If i go for a custom
driver in host side will my problem solved? Please suggest me a
solution for this.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/105408?ContentTypeID=1</link><pubDate>Tue, 25 Oct 2011 01:36:50 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:8d384902-9bf1-4d2a-8594-85daaf10ef90</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
No. There are 1000 frames / second, i.e. one every millisecond -
and with a very, very strict requirement on allowed jitter. Change
the oscillator frequency, and you will no longer have compatible USB
communcation.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/79695?ContentTypeID=1</link><pubDate>Tue, 25 Oct 2011 01:08:21 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:37777321-d557-4304-9e73-2a03259ff468</guid><dc:creator>jamiil libeyak</dc:creator><description>&lt;p&gt;&lt;p&gt;
can you make the oscilator jump fater?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Increasing speed in interrupt tranfer</title><link>https://community.arm.com/thread/67019?ContentTypeID=1</link><pubDate>Tue, 25 Oct 2011 00:50:12 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:60720c5e-0943-4644-8284-c4a19a91c556</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
Bulk transfer?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>