SD Sniffer

This board is a unique board recommended by a SparkFun customer. When playing with SD, you sometimes need to view what the SPI traffic is doing, whether for hacking or debugging. The SD Sniffer allows you to hook up an external device, such as a logic analyzer or microcontroller, to view what signals are being passed back and forth. Insert one side into a regular SD socket and a SD card into the SD holder, simple as that.

**Note: **This product is a collaboration and a portion of each sale goes toward the designer for product support and continued development.

SD Sniffer Product Help and Resources

Core Skill: Soldering

This skill defines how difficult the soldering is on a particular product. It might be a couple simple solder joints, or require special reflow tools.

1 Soldering

Skill Level: Noob - Some basic soldering is required, but it is limited to a just a few pins, basic through-hole soldering, and couple (if any) polarized components. A basic soldering iron is all you should need.
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Looking for answers to technical questions?

We welcome your comments and suggestions below. However, if you are looking for solutions to technical questions please see our Technical Assistance page.

  • What does this do? Take SPI data and save it to a SD card? Very hard to understand from the description.

  • Member #545155 / about 9 years ago / 1

    Why didn't I come to SparkFun first? I've been looking for something like this, but was having trouble finding what I wanted. This is close enough and I can now move forward with designing my project.

    What I was really looking for was a M/M cable so I could connect my CPAP to my device to directly load the data to private cloud storage without removing the SD card and then remembering to put it back. Now I won't have to write the original data to the SD card, I'll just have to sniff out the data and write it my way to the private cloud.

    • codekoala / about 7 years ago / 1

      This is exactly what I'm trying to figure out how to do. Did you come up with a solution? I would love to track metrics from my CPAP without having to bother the SD card every morning.

  • Member #242561 / about 10 years ago / 1

    What is the PCB thickness?.... 1.6mm or 2.0mm?

  • bfesser / about 10 years ago / 1

    Suggestion for board revision: silkscreen pinout on both sides. You're already paying for "" on the second side, so why not make more use of it? Actually, this suggestion applies to many other SFE boards...

  • Member #282982 / about 11 years ago * / 1

    Is it possible to cut the SD card portion of the PCB and make an extension cable to the holder portion?

    Edit: Well looks like you can. Simply ignore WP and CD.

  • jonny_nut / about 12 years ago / 1

    While I understand the Electric Imp isn't an actual SD card and only uses the same form factor, wouldn't this sniffer still be able to intercept what's being passed back and forth? Couldn't data be redirected to an alternate "mothership" as some call it?

    • jimblom / about 12 years ago / 1

      Sure, this is a very handy board for Imp troubleshooting.

      Keep an eye on the Imp's pin-out; the power and ground pins should match up, but that's about it.

      Also, you'll want to cut that jumper on the back of the Sniffer so as not to short pin 6 (where the Imp connects to the ID chip) to ground.

  • Far_Seeker / about 12 years ago / 1

    I just wanted to note that access to the additional pins is a welcome an appreciated change. :)

Customer Reviews

4.5 out of 5

Based on 2 ratings:

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Makes logic analysis much easier.

I used it together with a selea logic analyzer to fix a problem using SPI. It was very easy to do. Worked without a glitch.

SD sniffer

Makes it easy to debug. I am glad I ordered two sniffers. Insert/removal is fragile. One stopped locking the card after couple of inserts/removals. Not sure if it was because I am using a wifi card which is way more heavy than an SD Card. I also ordered micro SD card sniffer. It is working well.

Fill out a return ticket for the unit with the broken SD card latch and we may be able to get you a replacement: