<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>q3k</author><text>Data transfers in SD cards are CRC checked.&lt;p&gt;In addition, the card will by default start in a 12.5MB&amp;#x2F;s mode at 3.3v, which is 25MHz per lane. That&amp;#x27;s not DC, but it&amp;#x27;s definitely slow enough to run on some pretty dodgy wiring. It will only switch to higher speed modes if requested, and if it actually works (falling back to lower speeds otherwise).</text><parent_chain><item><author>castratikron</author><text>Oh, man. I&amp;#x27;m surprised that card works at all with that wiring. High speed single ended signaling does not do well off-board. Have you done any kind of integrity testing, like writing a GB to the disk and then reading the checksum?&lt;p&gt;If anyone is looking to do this mod, at least consider using a shielded ribbon cable like so:&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.amazon.com&amp;#x2F;LANMU-Extension-Flexible-Monoprice-Raspberry&amp;#x2F;dp&amp;#x2F;B01D9JIUU0&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.amazon.com&amp;#x2F;LANMU-Extension-Flexible-Monoprice-Ra...&lt;/a&gt;</text></item></parent_chain></comment><story><title>ReMarkable MicroSD (2019)</title><url>http://www.davisr.me/projects/remarkable-microsd/</url></story>
<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>reportingsjr</author><text>SD cards typical aren&amp;#x27;t run on a very high speed bus. A couple of MHz is pretty typical and this sort of wiring is no problem at those speeds.&lt;p&gt;Definitely no need for a shielded cable either.</text><parent_chain><item><author>castratikron</author><text>Oh, man. I&amp;#x27;m surprised that card works at all with that wiring. High speed single ended signaling does not do well off-board. Have you done any kind of integrity testing, like writing a GB to the disk and then reading the checksum?&lt;p&gt;If anyone is looking to do this mod, at least consider using a shielded ribbon cable like so:&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.amazon.com&amp;#x2F;LANMU-Extension-Flexible-Monoprice-Raspberry&amp;#x2F;dp&amp;#x2F;B01D9JIUU0&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.amazon.com&amp;#x2F;LANMU-Extension-Flexible-Monoprice-Ra...&lt;/a&gt;</text></item></parent_chain></comment><story><title>ReMarkable MicroSD (2019)</title><url>http://www.davisr.me/projects/remarkable-microsd/</url></story>