AP Computer Science Principles | SSH Remote Access (On Raspberry Pi)

Today, we got to use SSH to control a Raspberry Pi device. We had some technical difficulties at the start, but we soon managed to fix them. We also learned how to transfer files to and from the Raspberry Pi. For example, I sent the Pi a picture from my computer, and my partner took the file from the Pi and put it on his computer.


Screen Shot 2016-09-30 at 8.39.25 AM


This image shows the many times we tried to transfer pictures from my computer to the Pi.



I also learned how to delete folders/documents.

Screen Shot 2016-09-30 at 9.00.23 AM

This image shows how I deleted a folder called “meme”

AP Computer Science Principles | SSH Remote Access

SSH, or Secure Shell, allows a computer to establish a connection with another, and essentially control it.


Using this, we messed around with other people’s computers by making them say things out loud. We also learned how to open and delete files, as well as browse them.


We used a line of code to install the SSH, and then we connected it. We had to find the username, ip address, and password of the target computer to hack it. We used this code:

ssh user@hostname


Something interesting that we found was that even if you turn off remote access on terminal, if someone is already connected, they won’t be disconnected.


Ways that this could be used ethically is if you wanted to take down an evil person’s computer. If you wanted to control another one of YOUR OWN devices, you can, and it seems ethical.


Unethical things to do with this is to delete files on someone you dislike, or to do other things to mess with them.






AP Computer Science Principles | Pecha Kucha Reflection

I started this project by familiarizing myself with the topic. I did this by reading various articles (mostly just Wikipedia). I maybe spent a little bit too much time familiarizing, as I had less time to get pictures. This also left me with little to no time to actually prepare for the presentation. I got a lot of the pictures from Code.org. After getting all of these pictures and researching, I started to form an opinion about the subject.




Hoffman, Chris. “Hacker Hat Colors Explained: Black Hats, White Hats, and Gray Hats.” HowTo Geek RSS. How-To Geek, 20 Apr. 2013. Web. 22 Sept. 2016. <http://www.howtogeek.com/157460/hacker-hat-colors-explained-black-hats-white-hats-and-gray-hats/>.

Code.org. Code.org, n.d. Web. 22 Sept. 2016. <https://code.org/>.

Wikipedia. Wikimedia Foundation, n.d. Web. 22 Sept. 2016. <https://en.wikipedia.org/>.

AP Computer Science Principles | Unit One Blog

You will need to keep track of what you have learned in each lesson on a blog so when it comes to your PT (S) tasks you will be able to remember the activities that relate towards them.

Write a piece of reflection of things learned from each lesson. See sections below from unit one, things we have covered so far.


L2. Building your communication device and sending basic messages through the device.

I learned how to communicate without having to use the complicated words and sentences that we use in the English language. What I did was have a selection of different colored Lego bricks, which each represented a different answer. We would point to the one that represented our answer. If we had a green brick be “yes” and a red brick be “no” and I asked “Are you a human?” you would point to the green brick (probably).


L3. Sending 2 bit binary messages to each other using the internet simulator.

In this lesson I basically learned what binary is. I had no previous knowledge of what it was, and now I learned how to use two bits to convey a message with someone else. It was a slow process, but we managed to send simple messages to each other using just ones and zeroes.


L4. Number systems – creating number systems with symbols such as a square, triangle and circle to come up with as many permutations as possible. Look at the number systems reflection discussion.

This activity opened my eyes to the vast possibilities of different number systems. It showed me what happens when you throw more than two bits into a system and how to pinpoint the exact amount of possibilities using just the number of shapes or bits.


We also looked at Nibble, bit, byte, KB, MB, TB. define these.

Nibble: 1/2 a bit.

Bit: 1 bit

Byte: 8 bits.

Kilobyte: 1,000 bytes.

Megabyte: 1,000 kilobytes.

Gigabyte: 1,000 megabytes.

Terabyte: 1,000 gigabytes.


L5. Binary numbers – You made a Flippy do (take a picture of your flippy do) explain why this is useful to learning binary.

This “Flippy Do” is incredibly useful for learning binary. It’s kind of like a binary cheat-sheet of sorts. You just take the binary code, put it in the bottom part (using either ones or zeroes) and add up the numbers above all of the ones. The answer you get is the binary code converted to decimal.

Photo on 24-8-2016 at 10.31 AM

We looked at binary addition and subtraction.

Add your examples and explanation to the blog.


L6. Developing a number sending protocol.

Reflect on the process of sending numbers to your partner to create the shapes you have designed. See folder L6 discussions and homework. Add these to your blog.

We colored in squares to make a shape, then we sent each row as ones and zeroes to each other. Ones represented spots that were filled in, and zeroes represented spots that were empty. As we went through the rows, we eventually passed on the picture to each other.


Reflect on your learning in this lesson. In the space below, enter:
3 recollections (things you remember),

3) I remember converting a complicated sentence into html, then converting the html into ASCII.

2) I remember learning what ASCII even is.

1) I remember sending messages in ASCII between myself and my partner.

2 observations (things you noticed), and

2) I noticed that converting things into ASCII is very difficult and time consuming (at least by hand).

1) I noticed that as we go through more lessons, we are slowly learning more efficient ways of communicating messages.

1 insight (something you fully understand the…