b8

A simple USB keypad with 8 programmable buttons.

Motivation

I wanted to have a simple keypad I could use to control my computer.

I wanted to be able to write userspace programs in Golang, that would react to the keypress events in the keypad, and execute some programmed action, instead of building long sequences of keypress macros.

I wanted the PCB to be simple (PTH parts only), to have only the buttons and a single indicator LED, and to use the simplest/smallest microcontroller that could handle USB 1.1 and 8 buttons.

I wanted the enclosure to be 3D-printed at home.

I wanted it to be as USB HID compliant as possible, so I could learn more about it.

I wanted the client library to support Linux and Windows.

What is included

Pictures

Program examples

Simple

package main

import (
	"fmt"
	"log"
	"time"

	"github.com/rafaelmartins/b8/go/b8"
)

func main() {
	dev, err := b8.GetDevice("")
	if err != nil {
		log.Fatal(err)
	}

	if err := dev.Open(); err != nil {
		log.Fatal(err)
	}
	defer dev.Close()

	for i := 0; i < 3; i++ {
		dev.Led(b8.LedFlash)
		time.Sleep(100 * time.Millisecond)
	}

	dev.AddHandler(b8.BUTTON_1, func(b *b8.Button) error {
		fmt.Println("pressed")
		duration := b.WaitForRelease()
		fmt.Printf("released. pressed for %s\n", duration)
		return nil
	})

	if err := dev.Listen(nil); err != nil {
		log.Fatal(err)
	}
}

F.A.Q.

How to use this keypad to control `OBS`, similarly to what the `Stream Deck` does?

You can write event handlers that interact with OBS by using the goobs library: https://github.com/andreykaipov/goobs

b8