This is a really simple TinyGo project that relieaves certain worry when I travel and leave my aquarium unattended. Coupled with a Raspberry Pi with a camera, Wireguard tunnel, a couple of simple (reverse) proxies I am able to remotely care for my aquatic critters!

At first I was thinking what kind of hardware to use and how to connect it to the Internet, however, I was really stoked on doing this project using Go. So, ESP32 wifi capabilities were out the window until this and related issues are resolved. Then I was thinking whether to design the hardware and solder it myself... And then one day I remembered, that I've got a couple of M5StickC modules lying around without any interesting usecase.

Also, A few weeks ago, I created kind of a reminder using M5Stack Atom with experimental configurable Pomodoro timer and decided to expand on that. I took the M5StickC, experimental Pomodoro timer code, refactored it a bit, fiddled with FreeCAD and vuola! Remote-capable fish automation unit is complete with minimal soldering effort!

I really really really wait for TinyGo to have native WiFi capability on these chips! (Maybe Espressif will help?) This way I would be able to connect a camera module, integrate Wireguard and stream video/pictures without Raspberry Pi!

• Three individually resettable timers:
  • Feeding
  • water changes
  • filter maintenance
• Nudges
• Dispense food using a cheap 9g server
• Reset feeding timer and feed the fish (configurable feeding pattern)
• M5Stack IR temperature sensor
• Remote feeding and status (via USB, serial)

There are three timers:

• A timer to feed the fish (every 24h)
• A timer to do a water change (every week)
• A timer to do canister filter maintenance (3 months)

Once a timer is due, the screen and built in LED start to flash. In this case you can reset the timer by pressing the A button (the large button on M5Stick right to the screen). You can initiate a feeding sequence by long pressing the A button. This will reset feeding timer. Also, you can initiate food dispencing(once) without resetting the timer by long pressing the B button (a small button on the side of the M5Stick). You can reset any timer even if it is not due by short pressing the B button a few times until the timer is selected and then short pressing the A button to reset that timer.

The serial connection baud rate is 152000 and it accepts single character commands, such as:

• "f" - initiates the feeding sequence and resets the feeding timer
• "d" - dispenses food once
• "r" - reset current timer
• "1", "2" or "3" - reset specific timer
• "i" - show information about the timers (prints a list of ETA)
• "t" - show information about the temperature sensor. Prints out MLX90614 ID, configured Emissivity, ambient, Object1, and Object2 temperatures

You only need an Espressif IDF SDK and a proper version of esptool.py (on Windows it installs as esptool.py.exe which totally screws with the tooling for some reason, so I had to manually copy and rename the executable installed by pip). If your esptool is working and the M5StickC(or any ESP32 board for that matter!) is connected, you can run go generate and after brief compillation the firmware will be flashed.