# HITCON CTF Quals - 2019

## Misc / 221 - EV3 Arm

> 
>
> https://youtu.be/6Hb4KEqtboI
>
> [ev3_arm-17958868466f3801c4926675e13863b838e8e7cc.rbf](http://hitcon-2019-quals.s3-website-ap-northeast-1.amazonaws.com/ev3_arm-17958868466f3801c4926675e13863b838e8e7cc.rbf)
>
> Author: Jeffxx
>
> 48 Teams solved.

### Solution

By [@chuanchan](https://github.com/chuanchan1116)

The file provided is a binary that runs on Lego Mindstorms EV3. Using [this website](http://ev3treevis.azurewebsites.net/) to get a list of readable instructions. The Lego Mindstorms EV3 has 4 ports to connect to the motor. If you watch the video closely and compare to the picture provided in the description, you'll see that ports B connects to motor lifting or striking the pen, port A connects to motor for vertical stroke, and port C connects to motor for horizontal movements.

Comparing the instructions with the video, it's easy to speculate that `port_motor: B | rotations: 35 | speed: -15` strikes the pen, `port_motor: A | rotations: 720 | speed: -75` creates a stroke about height of `h`, `port_motor: C | rotations: 2 | speed: 70` create a stroke about width of `h`. Everytime a character is written, the pen will reset to the left top corner for the next letter. Trying to manipulate the instructions manually, and you will get the flag.

`flag:hitcon{why_not_just_use_the_printer}`

Instructions decoded are as follow

```
ev3_arm
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//h
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 180 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 180 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//i
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 90 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 450 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//t
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 4 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//c
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 3.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 420 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//o
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 300 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 320 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 400 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 420 | speed: 75
├─ FORK objectid: 3
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 60
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 480 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//n
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 660 | speed: 75
├─ CommentBlock
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 0.5 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 300 | speed: -75
├─ FORK objectid: 5
│ ├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 0.3 | speed: -90
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 0.3 | speed: 90
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 300 | speed: -75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 0.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//{
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ FORK objectid: 7
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2.2 | speed: 35
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 420 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//w
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 300 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//h
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ FORK objectid: 9
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2.2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 420 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 600 | speed: -75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 0.75 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//y
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 0.75 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 900 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
//_
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 400 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 420 | speed: 75
├─ FORK objectid: 10
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 60
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 480 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 700 | speed: 75
//n
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 3.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 420 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 300 | speed: 75
//o
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 90 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 450 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//t
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//_
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 180 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 180 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: -75
├─ FORK objectid: 12
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 180 | speed: 25
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 900 | speed: 75
//j
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 400 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: 75
├─ FORK objectid: 15
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 60
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 480 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 280 | speed: 75
//u
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 3.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ FORK objectid: 17
│ └─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -60
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 80
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -60
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//s
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 90 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 450 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//t
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//_
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 400 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: 75
├─ FORK objectid: 19
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 60
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 480 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 280 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 3.5 | speed: 70
//u
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ FORK objectid: 21
│ └─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -60
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 80
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -60
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//s
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 540 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 240 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 480 | speed: -75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 780 | speed: 75
//e
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//_
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 90 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 450 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//t
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//h
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 540 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 240 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 480 | speed: -75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 780 | speed: 75
//e
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//_
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 420 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 800 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 1100 | speed: 75
//p
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 400 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 420 | speed: 75
├─ FORK objectid: 22
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 60
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 60 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 280 | speed: 75
//r
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 180 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 180 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//i
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 400 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 420 | speed: 75
├─ FORK objectid: 24
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 60
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 480 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 700 | speed: 75
//n
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 90 | speed: 75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 450 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//t
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 540 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 240 | speed: 75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 480 | speed: -75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 780 | speed: 75
//e
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 360 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 400 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 420 | speed: 75
├─ FORK objectid: 27
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 1.5 | speed: 60
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 60 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 280 | speed: 75
//r
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 2 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: -15
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 0.5 | speed: 70
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 300 | speed: -75
├─ FORK objectid: 29
│ ├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 0.3 | speed: 90
│ └─ Motor.Rotations brake: 1 | port_motor: C | rotations: 0.3 | speed: -90
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 120 | speed: -75
├─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 300 | speed: -75
├─ Motor.Rotations brake: 1 | port_motor: C | rotations: 0.5 | speed: -70
├─ MediumMotor.Degrees brake: 0 | port_motor: B | rotations: 35 | speed: 15
└─ MediumMotor.Degrees brake: 0 | port_motor: A | rotations: 720 | speed: 75
//}
```

Original writeup (https://github.com/10secTW/ctf-writeup/blob/master/2019/HITCON%20CTF/EV3%20Arm/ev3%20arm.md).