RubberJogi

What is the idea / the usecase ?

• You want to control a PC from another PC, making keystrokes, eventually mouse-moves.
• Even when starting up and e.g. entering the BIOS
• => ssh etc not an option
• you need to be independent from any "client" on the controlled machine
• only solution which comes to mind is : USB HID
• Therefore you connect from PC I somehow to PC II, on PC II as USB-Keyboard

Solution : RubberJogi

+----------------+                                  +----------------+
|                |                                  |                |
|    PC I        |                                  |    PC II       |
|                |          +-------------+         |                |
|  (Controller)  | USB      |             |  USB    |  (Worker)      |
|                +--------->+ RubberJogi  +-------->+                |
|                | serial   |             |  HID    |                |
|                |          +-------------+         |                |
|                |                                  |                |
+----------------+                                  +----------------+

• PC I connects to RubberJogi via USB-Serial
• RubberJogi injects Keystrokes etc via USB HID to PC II

Ingredients Hardware

• Arduino ( with USB-Keyboard capability), e.g. Leonardo, Micro, etc

• USB-TTL UART Converter , FTDI Serial

• some cables

  

  

Ingredients Software

• As it is not possible to send CMD-Keys like ALT, CTRL via serial line, a language has to be used.
• Avoid to reinvent the wheel ==> Compatible to the famous RubberDucky-Script-Language
• ==> Based on arducky by Baptiste MOINE (Creased), THANKS!
• Parser is based on https://github.com/Creased/arducky/blob/master/arducky.ino
• is partially extended for also sending MOUSE-Movements
• is already extended to control four additional GPIO-Switches
• Accepted Commands :
  • All RubberDucky-Commands (not really all...)
  • backspace
  • switch1_on / switch1_off => switching Optocoupler at Pin2
  • switch2_on / switch2_off => switching Optocoupler at Pin4
  • switch3_on / switch3_off => switching Optocoupler at Pin6
  • switch4_on / switch4_off => switching Optocoupler at Pin8
  • boot => switching Optocoupler at Pin2 for 1.5 sec high, then low
  • reboot => switching Optocoupler at Pin2 for 10sec high, then low, after a delay of 2 secs then once more for 1.5 sec high, then low
  • aten => switching Optocoupler at Pin4 for 1.5 sec high, then low

Controlling

For "talking" to the RubberJogi from PC1 you need to configure your serial port to

• 9600 Baud
• 8 Bit, 1 Stop-Bit, No parity

If you are using a linux-box you could use the follwing command to achieve this:

stty -F /dev/ttyUSB0 cs8 9600 ignbrk -brkint -icrnl -imaxbel -opost -onlcr -isig -icanon -iexten -echo -echoe -echok -echoctl -echoke noflsh -ixon -crtscts
Then you can just try out the functionality of the box with e.g :

• echo "ENTER" > /dev/ttyUSB0 when you are allowed to use /dev/ttyUSB, or
• echo "ENTER" | sudo tee /dev/ttyUSB0 when you need to be root to use /dev/ttyUSB

In both cases you should see a moving text-cursor on the second PC (best open an Editor...)

Special Hardware with 2 switches

• In our/my usecase we also need to control two switches

• one of these is connected to the reset-button of the PC

• the other one is connected to the switch of a USB-sharing station, so we can switch a USB-stick between PC1 and PC2 ...

• more explanations will follow, the code is already able to make use of these

• here at least are the schematics

• In case you want (like we do) to switch on PC2 with a command from PC1 you need to connect Vcc between FTDI and Arduino, otherwise the Arduino will not have power when he is connected to a switched of PC ... ( see the green cable below)

• Unfortunately, it looks like this is backfeeding 5V even to the 2nd PC via USB. This is not a problem if the PC is switched on. BUT : If you have the PC switched off and want to switch it on, then - depending on the PC - it might make some trouble for the PC, as it is never really switching completely off. I need to try this remedy : https://forum.arduino.cc/t/powering-the-arduino-with-a-5v-power-supply/261902/12

• We tried out this remedy (remove T1 of the ARDUINO) and it works perfect. BUT beware: when you want to re-programm the Arduino you NEED to have the FTDI connected as well to a PC, as otherwise the Arduino is not powered...

• See here the location of the T1 to be removed:

  

  

Extended Special Hardware with 4 switches

• in the meantime we even have use-cases where we need to control up to 4 switches

• as before one of these is connected to the reset-button of the PC (in our case)

• as before one is connected to the switch of a USB-sharing station, so we can switch a USB-stick between PC1 and PC2 ... (in our case)

• the other 2 switches are needed to control boot-sel switches of embedded ARM systems

• here are the additional schematics

• In case you want (like we do) to switch on PC2 with a command from PC1 you need to connect Vcc between FTDI and Arduino, otherwise the Arduino will not have power when he is connected to a switched of PC ... ( see the green cable below)

• backfeeding 5V via USB to PC2: see above at the 2-Switch-Solution)

  

  

Extended Special Hardware with 5 switches and one relay

• finally (in our application) we need to switch power
• we introduced a 5th optocoupler, connected to pin10 AND we connected a real relay to that to be able to switch power
• schematics will follow

Reality

This is one sample-prototype without any switches, just the "plain" RubberJogi. This was soldered "flying" and is only stabilized with heat shrink tube.

This is one sample-prototype, with 4 switches, soldered on a veroboard/breadboard

These are all 3 prototypes I have built, together on one picture.

• 2 times extended RubberJogis with 4 switches
• 1 as a pure RubberJogi, no switches.

Parts-List

What do you need to build a RubberJogi?

Part	Rubber Jogi Standard	Rubber Jogi Two Switch	Rubber Jogi Four Switch
Arduino Micro	1	1	1
FTDI USB / Serial Converter 5V capable	1	1	1
Cables between Arduino/FTDI (Vcc, GND, RxD, TxD)	4	4	4
USB-Cable to Arduino (USB-A to Micro-USB)	1	1	1
USB-Cable to FTDI (USB-A to Mini-USB)	1	1	1
Veroboard	?	ca 60x50 mm	ca 60x50mm
Header Arduino (when not using already w/ headers)	?	34	34
Header FTDI	?	18	18
Optocoupler 4N25 DIL	0	2	4
Resistor 390 Ohm	0	2	4
Connectors, depends on your needs, e.g	0	2	4
Example: Headers for switches	0	4	8

Links, Ideas

• Mouse-Support currently missing to 90%, positioning does not work. Maybe move to USB-Touch-Screen could solve the problem? Please have a look at this project, might be worth checking out : https://github.com/NicoHood/HID
• Another potential usefull link to solve the mouse-move would be : https://www.codeproject.com/Articles/1001891/A-USB-HID-Keyboard-Mouse-Touchscreen-emulator-with