# CubeSatSim

The CubeSat Simulator https://github.com/alanbjohnston/CubeSatSim/wiki is a low cost satellite emulator that runs on solar panels and batteries, transmits UHF radio telemetry, has a 3D printed frame, and can be extended by additional sensors and modules.  This project is sponsored by the not-for-profit [Radio Amateur Satellite Corporation, AMSAT®](https://amsat.org).

Requires:
- wiringpi
- libcurl4-openssl-dev
- git

See the Wiki Software Install page for more details: https://github.com/alanbjohnston/CubeSatSim/wiki/Software-Install. To build and run the software on a Raspberry Pi 3B, 3B+, or Pi Zero W:
Requires:
- Raspbian Stretch or Buster, full desktop or Lite 
- wiringpi
- git
- libasound2-dev
- pi-power-button
- Direwolf
- rpitx

See the Wiki Software Install page for more details: https://github.com/alanbjohnston/CubeSatSim/wiki/Software-Install. To build and run the software on a Raspberry Pi 3B, 3B+, or Pi Zero W (Does NOT work on a Pi 4 since rpitx does not work on it yet):

`sudo apt-get install -y wiringpi git libasound2-dev i2c-tools`

Run raspi-config and enable the I2C bus by selecting Option 5 Interfacing Options and then Option 5 I2C and selecting Y to enable the ARM I2C bus:

`sudo raspi-config`

Select Finish at the bottom to exit raspi-config. Then type:

`sudo cp /boot/config.txt /bootconfig.txt.0`

`sudo nano /boot/config.txt`

Use the down arrow key to go down in the file until you find this line:

`# Additional overlays and parameters are documented /boot/overlays/README `

Add the following two lines under it:

`dtoverlay=i2c-gpio`

`dtparam=i2c_vc=on`

Press Ctrl-X then type `y` then hit Enter to save the file and exit the editor. You should back at the pi@... prompt. Reboot by typing:

`sudo reboot now`

after logging back into the Pi, type:

`ls -a /dev/i2c*`

you should see three I2C buses:

`i2c-0 i2c-1  i2c-3`

Continue the install by typing:

`cd`

Then type:

`git clone http://github.com/alanbjohnston/CubeSatSim.git`

`cd CubeSatSim`

Where <branch> is the name of this branch of the software, type:

`git checkout <branch>`

Edited the sim.cfg file to set your amateur radio callsign, then 

`make rebuild`

`git clone https://www.github.com/wb2osz/direwolf`

`cd direwolf`

`make -j`

(takes a while)

`sudo make install`

`make install-rpi`

Note that this last command may fail if you are using Raspbian Lite since there is no Desktop.

`cd ~/CubeSatSim`

`git clone https://github.com/F5OEO/rpitx.git`

`cd rpitx`

`./install.sh`

(Takes a while).  It will prompt you if you want to modify /boot/config.txt file.  Type a `y` and the script will complete.

`cd ~/CubeSatSim`

`git clone https://github.com/alanbjohnston/pi-power-button.git`

`cd pi-power-button`

`cp ../python/listen-for-shutdown.py listen-for-shutdown.py`

`./script/install`

To make the demo.sh script run automatically on boot:

`sudo cp /CubeSatSim/systemd/cubesatsim.service /etc/systemd/system/cubesatsim.service`

`sudo systemctl enable cubesatsim`

Now reboot for all the changes to take effect:

`sudo reboot now`

After rebooting, to hear AFSK telemetry (X.25 data), tune your radio or SDR to 434.9 MHz FM, and you should receive telemetry from the CubeSat Sim:


This code uses the Brandenburg Tech Digital Transceiver, based on DigitalTxRxRP  https://brandenburgtech.wordpress.com/ If you don't have the SPI Interface enabled and the board plugged in, you will get an error.

This repository contains:
     
  - afsk - Code that sends telemetry in 1k2 AFSK X.25 format
 - arduino - Sample Arduino sketches to show how payload sensors can be interfaced to CubeSat Simulator
 - ax5043 - Source for a library of functions to communicate with the AX5043 and configure the AX5043.
 - cw - Code that sends telemetry in CW (Morse code) using AO-7 format
 - libs - External libraries
 - python - Python code for reading I2C sensors for current and temperature
 - spreadsheet - Spreadsheets for decoding and analyzing the Simulator telemetry (see https://github.com/alanbjohnston/CubeSatSim/wiki/Decoding-Telemetry for details)
 - wav - Wave audio files of CW or AFSK telemetry for listening or transmitting usng a CubeSat Simulator Lite
 - demo.sh - a shell script to run the Simulator on boot using systemd (see https://github.com/alanbjohnston/CubeSatSim/wiki/Software-Install#autoboot-configuration for how to configure the Pi)

See the Wiki for more details https://github.com/alanbjohnston/CubeSatSim/wiki