Simchair MKIII I2C master controller is the main “brain” of the set: it detects connected devices automatically and then loads device-specific configuration. It uses an Arduino Leonardo board. There are several cool things about it:
- device-specific configuration
- external I2C ADCs for flight stick gimbal and pedals
- unified interface for everything, buttons or axes
- peripheral-specific software-driven special features
- new features are added to the software frequently
- Joystick library by MHeironymus, which simplifies things like ten times; no need to mess with USB descriptors
I don’t think there’s any point in using an old analog version anymore, as there are now controllers with buttons (an old UNO – based analog controller only supported six axes as it had to do some massive filtering because of a noisy 10 bit built-in ADC)
1 * Arduino Leonardo
4 * M3x50mm screws
4 * M3x12mm screws
2 * M3x16mm screws
6 * M3 nuts
3 to 8 * TJ8-8P8 sockets
- housing lids with 6 and 8 Ethernet socket slots
Flashing and configuration tutorial
- Remove supports from printed parts.
- Press-fit M3 nuts into their sockets in the enclosure bottom part.
- Inser Arduino Leonardo board into the enclosure and fasten with 4 M3x12mm screws.
- Solder 4-wire cables cut off the ribbon to 1st 4 pins of Ethernet sockets (pin 1 is where the orange-white wire is in the plug, pin 2 is the next one in another row, housing lids with slots for 3 to 8 sockets are available under Mods directory, we will be using a default 3-socket lid for this tutorial)
- Tie wires together by their pin numbers, and use another 4-wire cable to connect sockets to the board. Split that 4th cable into 22-wire cables and solder 2-pin headers to its ends. Use hot glue and insulation to strengthen them.
- Connect sockets to the board (5v, GND, SCL, SDA pins), flash it and check that all sockets work by plugging something to it (after re-plugging stuff, reset the board). If everything works, go on!
- Press-fit sockets into the lid and pour enough hot glue to fix everything in place properly.
- Connect pin headers to the board and put the lid on, use 4 M3x50mm screws to fix it.
- Insert 2 M8x50mm bolts into the mount part 1. Fix with nuts from the other side.
- Attach the mount to the controller housing with 2 M3x16mm screws (MAX 20mm!) . Put part 2 of the mount onto its bolts.
Congratulations, you have finished the master controller assembly!
We will be using this connection scheme for all of our devices:
SOCKET PIN 1 – VCC
SOCKET PIN 2 – GND
SOCKET PIN 3 – SCL
SOCKET PIN 4 – SDA
You can try flying with it right now, or read about firmware configuration.