package redbutton //go:generate stringer -type=Button import ( "errors" "time" "github.com/karalabe/hid" ) const ( vendor = 0x1d34 product = 0x000d ) type Button int const ( Unknown Button = iota Closed Pressed Armed ) func State(dev *hid.Device) (Button, bool) { buf := make([]byte, 8) buf[0] = 0x01 buf[7] = 0x02 if _, err := dev.Write(buf); err != nil { return Unknown, false } if _, err := dev.Read(buf); err != nil { return Unknown, false } if buf[7] != 0x03 { return Unknown, false } return Button(buf[0] & 0x03), true } func Poll(dev *hid.Device) <-chan Button { ch := make(chan Button) go func() { prev := Unknown tick := time.NewTicker(200 * time.Millisecond) defer tick.Stop() for range tick.C { if state, ok := State(dev); ok { if state != prev { ch <- state } prev = state } } }() return ch } func Open() (*hid.Device, error) { devs := hid.Enumerate(vendor, product) if len(devs) == 0 { return nil, errors.New("not found") } return devs[0].Open() }