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    <title>i.MX ProcessorsのトピックRe: i.MX6 enhanced transmit buffer - Protocol Specific Checksum failure</title>
    <link>https://community.nxp.com/t5/i-MX-Processors/i-MX6-enhanced-transmit-buffer-Protocol-Specific-Checksum/m-p/416705#M62622</link>
    <description>&lt;HTML&gt;&lt;HEAD&gt;&lt;/HEAD&gt;&lt;BODY&gt;&lt;P&gt;Hi,&lt;/P&gt;&lt;P&gt;I could solve the problem. It is no hardware issue. The problem was that I did not clear the checksum field in all cases, thus a random behavior apperared.&lt;/P&gt;&lt;/BODY&gt;&lt;/HTML&gt;</description>
    <pubDate>Mon, 20 Jul 2015 14:36:43 GMT</pubDate>
    <dc:creator>sammy</dc:creator>
    <dc:date>2015-07-20T14:36:43Z</dc:date>
    <item>
      <title>i.MX6 enhanced transmit buffer - Protocol Specific Checksum failure</title>
      <link>https://community.nxp.com/t5/i-MX-Processors/i-MX6-enhanced-transmit-buffer-Protocol-Specific-Checksum/m-p/416704#M62621</link>
      <description>&lt;HTML&gt;&lt;HEAD&gt;&lt;/HEAD&gt;&lt;BODY&gt;&lt;P&gt;Hi,&lt;/P&gt;&lt;P&gt;for an avionic project I am sending UDP packets with a UDP data length of 179, 181, 177 bytes from the i.MX6 to a client computer. &lt;/P&gt;&lt;P&gt;I have programmed the i.MX6 bare-bone including the ENET driver and the UDP/IP stack.&lt;/P&gt;&lt;P&gt;The Ethernet packages are send using the enhanced transmit buffer descriptors with full hardware accelerator support enabled (TC, PINS and INS). In addition the application specific flags TO1, R, and L are enabled.&lt;/P&gt;&lt;P&gt;I am sending 3 different UDP packages in a loop with 1000 iterarions and with a waiting time of 2 seconds between each package.&lt;/P&gt;&lt;P&gt;Although I am sending always the same 3 packages (UDP data) I can see on Wireshark that the UDP checksum is sometimes incorrect (please have a look on the attached screen shot).&lt;/P&gt;&lt;P&gt;But for the exact same package it is sometimes correct and sometime incorrect. I looks really like a hardware bug.&lt;/P&gt;&lt;P&gt;Can you please help ? Is this a known issue ?&lt;/P&gt;&lt;P&gt;Thank you in advanced.&lt;/P&gt;&lt;P&gt;Sammy&lt;/P&gt;&lt;P&gt;&lt;span class="lia-inline-image-display-wrapper" image-alt="udp_ckecksum_calc_failure_of_same_data.PNG"&gt;&lt;img src="https://community.nxp.com/t5/image/serverpage/image-id/58656i5BB3AA24245EF02A/image-size/large?v=v2&amp;amp;px=999" role="button" title="udp_ckecksum_calc_failure_of_same_data.PNG" alt="udp_ckecksum_calc_failure_of_same_data.PNG" /&gt;&lt;/span&gt;&lt;/P&gt;&lt;/BODY&gt;&lt;/HTML&gt;</description>
      <pubDate>Thu, 16 Jul 2015 12:07:25 GMT</pubDate>
      <guid>https://community.nxp.com/t5/i-MX-Processors/i-MX6-enhanced-transmit-buffer-Protocol-Specific-Checksum/m-p/416704#M62621</guid>
      <dc:creator>sammy</dc:creator>
      <dc:date>2015-07-16T12:07:25Z</dc:date>
    </item>
    <item>
      <title>Re: i.MX6 enhanced transmit buffer - Protocol Specific Checksum failure</title>
      <link>https://community.nxp.com/t5/i-MX-Processors/i-MX6-enhanced-transmit-buffer-Protocol-Specific-Checksum/m-p/416705#M62622</link>
      <description>&lt;HTML&gt;&lt;HEAD&gt;&lt;/HEAD&gt;&lt;BODY&gt;&lt;P&gt;Hi,&lt;/P&gt;&lt;P&gt;I could solve the problem. It is no hardware issue. The problem was that I did not clear the checksum field in all cases, thus a random behavior apperared.&lt;/P&gt;&lt;/BODY&gt;&lt;/HTML&gt;</description>
      <pubDate>Mon, 20 Jul 2015 14:36:43 GMT</pubDate>
      <guid>https://community.nxp.com/t5/i-MX-Processors/i-MX6-enhanced-transmit-buffer-Protocol-Specific-Checksum/m-p/416705#M62622</guid>
      <dc:creator>sammy</dc:creator>
      <dc:date>2015-07-20T14:36:43Z</dc:date>
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