The Pit

Simple arduino-based gamepad to connect custom switches and toggles and easily bind into DCS (uses standard mappings, nothing fancy).

Supports hundreds of switches on a single arduino board.

Relies on HC165N Parallel-Load Shift Registers, which are inexpensive ICs, to achieve a high number of inputs.

Firmware

Arduino-based program to manage a Sim Pit efficiently. The code is setup to be able to handle hundreds of inputs over a single Arduino chip, via the use of shift registers and SPI.

The recommended and target board is Leonardo.

Setup

• Download and install Arduino IDE v2
• Copy the firmware/hardware folder to your local Arduino install, ie %USERPROFILE%/Documents/Arduino/.
  • In the end, you should have a %USERPROFILE%/Documents/Arduino/hardware/thepit/avr/boards.txt file.
  • You can verify it works if your Arduino can locate a The Pit (Leonardo) board.

Uploading

Because the software is trying to maximize available inputs, it eats up the endpoints that are used to upload a sketch any time. Reset the board during the Upload... phase, otherwise it will fail.

Customizing

Customizable values, such as the number of daisy-chained hc165, how many gamepads we're emulating, etc, are available in thepitconfig.user.h.

Hardware

Daisy-chained hc165 Board

A simple board to easily daisy-chain several hc165 together. Each board has 4 connectors:

• 1x daisy chain in, that you connect from the out of the previous board (or from the arduino board)
• 1x daisy chain out, that you connect to the in of the next board (or to the receiving end of the arduino board)
• 2x inputs, each with 4x inputs and 1x ground, that you connect to your switches (pull-up logic, integrated to the board).

Wiring

Pin 5 is used to latch the hc165, use the ICSP pins for SPI communication. On the board, the pins from the connector are labeled with their usage:

• Vcc: 5V in
• GND: Ground
• ~PL: Pulse Latch (Pin 5)
• CP: Clock Pulse (SCK, pin 3 on the ICSP)
• DS: Data Serial in (for daisy chain in) (COPI, pin 4 on the ICSP for the first in the chain)
• Q7: Data serial out (for daisy chain out) (CIPO, pin 1 on the ICSP for the last in the chain)

Licenses

Firmware is released under the Mozilla Public License 2.0 Hardware designs are Open Hardware, licensed under CERN-OHL-W v2 or later