> For the complete documentation index, see [llms.txt](https://purplebyteone.gitbook.io/index/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://purplebyteone.gitbook.io/index/notes/education/base/purple-team/htb/challenges/retired/challenges/hardware/very-easy/secure-digital.md).

# Secure Digital

* <https://www.geeksforgeeks.org/process-table-and-process-control-block-pcb/>

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{% embed url="<https://www.saleae.com/downloads/>" %}

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{% embed url="<https://www.youtube.com/watch?v=XhWKoFj_p9k>" %}

{% embed url="<https://www.youtube.com/watch?v=nfcBitFcvkw>" %}

{% embed url="<https://www.youtube.com/watch?v=Ak9R4yxQPhs>" %}

{% embed url="<https://www.youtube.com/watch?v=8BJm2l6arR0>" %}

{% embed url="<https://circuitdigest.com/tutorial/serial-communication-protocols>" %}

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{% embed url="<https://electronics.stackexchange.com/questions/55960/difference-between-miso-mosi-and-txd-rxd>" %}

{% embed url="<https://en.wikipedia.org/wiki/Serial_Peripheral_Interface>" %}

I must admit that I went it to the rabbit hole too deep.

It was in front of me all the time:

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Basically, I got the flag and I can just write it in, but what else can I do?

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Hold ctrl and click on H to get to the table view

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Now I should be able to export it as txt file and get the flag out.

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Time to cleanup. It's easy task for Linux, but I'm lazy now to boot in VM so let's do that via Notepad++. Flag starts on the line 2287. Hope I don't leak that I use Windows and Notepad++ if you have 0day for them :drum:

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Let's remove SPI part

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Same way, last part. I'm sure it can be done in different way too.

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Just replace these patterns with simple " " space. Same way remove " " before chars and last " at the end. Now we need to change line output.&#x20;

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Do ctrl+c, ctrl+a, ctrl+v

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And, you can "Replace with:" just don't add anything, leave it empty.

Most important parth here where to understand what is what to get the correct sequence and find the information required.

Initially int felt hard, but once you have first time hands on - it will easy, but for first time I felt it hard.
