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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>Odd situation with USB Communication Device (CDC )- VCP</title><link>https://community.arm.com/developer/tools-software/tools/f/keil-forum/29648/odd-situation-with-usb-communication-device-cdc---vcp</link><description> 
Hi all, 

 
I’m having an odd situation with RL-USB with the following
characteristics: 

 
STM23F407ZG (board with proven hardware) 
Communication Device (CDC) – Virtual COM Port 
Full Speed 

 
CDC Config (in usb_config_FS.c): 
#define USBD_CDC_ENABLE</description><dc:language>en-US</dc:language><generator>Telligent Community 10</generator><item><title>RE: Odd situation with USB Communication Device (CDC )- VCP</title><link>https://community.arm.com/thread/140432?ContentTypeID=1</link><pubDate>Tue, 26 Feb 2013 08:14:55 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:26874870-ea06-4947-a93f-dfaa069ce257</guid><dc:creator>Bryce Johnson</dc:creator><description>&lt;p&gt;&lt;p&gt;
Thanks for the reply! I&amp;#39;ll look in to doing the upgrade and see if
that fixes it.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Odd situation with USB Communication Device (CDC )- VCP</title><link>https://community.arm.com/thread/131138?ContentTypeID=1</link><pubDate>Tue, 26 Feb 2013 06:58:35 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:7ea09a26-3f37-419c-9977-d0e9a12c75de</guid><dc:creator>Paulo de Almeida</dc:creator><description>&lt;p&gt;&lt;p&gt;
Hi Bryce,&lt;/p&gt;

&lt;p&gt;
I did not find a workaround this problem in the RL-USB, the good
news is that Keil did address the issue in the last version of MDK
(Version 4.70) and the RL-USB CDC module has been rewritten and it
now works great ! This new version finaly solved this and some other
issues. I now have a composite device (Mass Storage and VCP) working
just fine, I highly recommend you to upgrade :)&lt;/p&gt;

&lt;p&gt;
Follow this link to the MDK Version 4.70 release notes:&lt;br /&gt;
&lt;a href="http://www.keil.com/update/whatsnew.asp?p=RVMDK&amp;amp;v=4.70"&gt;http://www.keil.com/update/whatsnew.asp?p=RVMDK&amp;amp;v=4.70&lt;/a&gt;&lt;/p&gt;

&lt;p&gt;
Regards,&lt;br /&gt;
Paulo&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Odd situation with USB Communication Device (CDC )- VCP</title><link>https://community.arm.com/thread/127866?ContentTypeID=1</link><pubDate>Thu, 21 Feb 2013 10:41:24 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:dfa4ac7b-720e-4e87-b910-ab6d4a494724</guid><dc:creator>Bryce Johnson</dc:creator><description>&lt;p&gt;&lt;p&gt;
Also, I am on a LPC2478 with this tool chain.&lt;/p&gt;

&lt;p&gt;
Tool Version Numbers:&lt;br /&gt;
Toolchain: MDK-ARM Professional Version: 4.60.0.0&lt;br /&gt;
Toolchain Path: C:\Keil\ARM\ARMCC\bin\&lt;br /&gt;
C Compiler: Armcc.Exe&lt;br /&gt;
Assembler: Armasm.Exe V5.02.0.28&lt;br /&gt;
Linker/Locator: ArmLink.Exe V5.02.0.28&lt;br /&gt;
Librarian: ArmAr.Exe V5.02.0.28&lt;br /&gt;
Hex Converter: FromElf.Exe V5.02.0.28&lt;br /&gt;
CPU DLL: SARM.DLL V4.60.0.0&lt;br /&gt;
Dialog DLL: DARMP.DLL V1.51&lt;br /&gt;
Target DLL: ULP2ARM.DLL V2.18.0.0&lt;br /&gt;
Dialog DLL: TARMP.DLL V1.51&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Odd situation with USB Communication Device (CDC )- VCP</title><link>https://community.arm.com/thread/117065?ContentTypeID=1</link><pubDate>Thu, 21 Feb 2013 10:39:07 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:bf795725-1719-47a9-b569-6a559d42ee85</guid><dc:creator>Bryce Johnson</dc:creator><description>&lt;p&gt;&lt;p&gt;
Did you ever find any resolution to this? I am also seeing oddness
with usbd_cdc_ser_read not getting called after a number of bytes.
usbd_cdc_write is still working just fine.&lt;/p&gt;

&lt;p&gt;
I haven&amp;#39;t dug into it as far as you, but this popped up when I did
a google search.&lt;/p&gt;

&lt;p&gt;
Thanks&lt;br /&gt;
Bryce&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Odd situation with USB Communication Device (CDC )- VCP</title><link>https://community.arm.com/thread/106558?ContentTypeID=1</link><pubDate>Fri, 07 Dec 2012 17:10:59 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:e8cd1f40-f18c-4b3c-aab6-d15de7cbeffc</guid><dc:creator>Paulo Almeida</dc:creator><description>&lt;p&gt;&lt;p&gt;
Hi,&lt;/p&gt;

&lt;p&gt;
We have tried every situation and the problem still remains.&lt;/p&gt;

&lt;p&gt;
The last URB to the host is the following:&lt;br /&gt;
-- URB_FUNCTION_BULK_OR_INTERRUPT_TRANSFER:&lt;br /&gt;
PipeHandle = 89a949cc [endpoint 0x00000082]&lt;br /&gt;
TransferFlags = 00000003 (USBD_TRANSFER_DIRECTION_IN,
USBD_SHORT_TRANSFER_OK)&lt;br /&gt;
TransferBufferLength = 00000000&lt;br /&gt;
TransferBuffer = 8971b004&lt;br /&gt;
TransferBufferMDL = 89cad538&lt;br /&gt;
UrbLink = 00000000&lt;/p&gt;

&lt;p&gt;
TransferBufferLength is zero, and it should be 12 as in all the
previous IN URB to the host, at some point RL-USB just quits sending
more data.&lt;/p&gt;

&lt;p&gt;
We have even tried the examples supplied by Keil and the problem
still occurs, it&amp;rsquo;s strange that anyone has not reported this
before.&lt;/p&gt;

&lt;p&gt;
We were really looking forward to use RL-USB, but it seems that we
are at a dead end.&lt;/p&gt;

&lt;p&gt;
&lt;b&gt;Is anyone using RL-USB Communication Device (CDC) with success
?&lt;/b&gt;&lt;/p&gt;

&lt;p&gt;
Best regards,&lt;br /&gt;
Paulo&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Odd situation with USB Communication Device (CDC )- VCP</title><link>https://community.arm.com/thread/92168?ContentTypeID=1</link><pubDate>Thu, 01 Nov 2012 20:36:19 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:1f8a2316-b907-4411-83e9-f72f63a4fdc5</guid><dc:creator>Chinzei Tsuneo</dc:creator><description>&lt;p&gt;&lt;p&gt;
Confirm that host is still polling the target bulk IN endpoint or
not.&lt;/p&gt;

&lt;p&gt;
On a hardware bus analyzer, the bulk IN endpoint is NAKing.&lt;br /&gt;
or&lt;br /&gt;
On a software sniffer, confirm that the last URB to the bulk IN
endpoint is pending, without any error.&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: Odd situation with USB Communication Device (CDC )- VCP</title><link>https://community.arm.com/thread/61327?ContentTypeID=1</link><pubDate>Wed, 31 Oct 2012 15:11:33 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:738da12c-ba03-455f-ad27-4f50326bc9c8</guid><dc:creator>Paulo Almeida</dc:creator><description>&lt;p&gt;&lt;p&gt;
Hi again,&lt;/p&gt;

&lt;p&gt;
in addendum to my previous post I should say that
&amp;ldquo;usbd_cdc_ser_availchar&amp;rdquo; is still reporting that there
are more char to send but still &amp;quot;usbd_cdc_ser_read&amp;quot; is not
called.&lt;/p&gt;

&lt;p&gt;
Thanks,&lt;br /&gt;
Paulo&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>