---
title: "Big shiny arcade buttons"
date: 2019-11-05T08:20:43+01:00
draft: false
summary: Adding buttons to my "smart desk"
images: [/static/img/buttons-anim.gif, /static/img/buttons-aus.jpg, /static/img/buttons-switches-marked.jpg]
---
Last [post]({{< ref "/posts/desk-automation.md" >}}) i teased the next upgrade of my smart desk project which are some big arcade buttons to control the light even when my network is down. Well... 

I finished that part over the last few days:

{{< figure src="/img/buttons-aus.jpg">}}

The buttons i did choose for the desk are thous big arcade buttons[^1] as they produce this satisfying click when pressed. They come with an integrated LED and resistor, but -as they are not supposed to be driven by a 3.3 volt microcontroller- they need 12 volt supplied to be fully lit up. For the controller i use a normal USB power supply so i tried to power the LEDs with 5 volts.  That made them bright enough so i went with that...

The button comes in 2 parts which have to be assembled together. The first part is the thing you actually press (which also lets the light pass) and the second part is the Switch+LED combo. To make a neat package i modified the second part. By modified i mean i soldered a transistor to the pins to up the 3.3V logic level from the GPIOs of the controller to 5V needed for the LED. For that i just used a normal 2N2222 NPN-Transistor[^2]. 

Soldered together the switches + transistor + some cables the "thing" looks something like this:
{{< figure src="/img/buttons-switches-marked.jpg">}}

The transistor is marked red, as the photo is to potato-quality to make it out otherwise :D

| pin       | connected to 
| -----------|------
|  1 | GPIO (Switch) 
|  2 | 3.3V 
|  3 | 5V 
|  4 | GPIO (LED) 
|  5 | GND 

after hooking it up the the controller i had to change and add some parts of the configuration yaml of the esphome-firmware:
```yaml
light:
  - platform: monochromatic
    name: "Rote Led"
    output: led_rot
    id: rotled

output:
  - platform: ledc
    id: led_rot
    pin: 14

binary_sensor:
  - platform: gpio
    pin: 
      number:  12
      inverted: True
      mode: INPUT_PULLUP
    name: "ButtonRot"
    filters:
      - delayed_on: 20ms
    on_click:
      min_length: 5ms
      max_length: 500ms
      then:
        - switch.toggle: relay1

switch:
  - platform: gpio
    pin: 
      number: 33
      inverted: True
    name: "Schreibtischlampe"
    id: relay1
    on_turn_on:
      then:
        - light.turn_on:   
            id: rotled  
            transition_length: 200ms
    on_turn_off:
      then:
        - light.turn_off: 
            id: rotled
            transition_length: 500ms
```

The added parts in the on\_turn\_{on,off} sections of the switch turn the LED {on,off}.
By hooking them up to the switch activation and not the button press the leds also turn on when the relay gets activated via the webserver. 
The "transition_length: ...ms" parameter makes the LED fade in and out smoothly (only works on an PWM GPIO).

After that there only was a case to design and 3D print. I settled for the classic highly complex[^3] box shape design as you can see in the image above.

As you can see in the image i have another blue button next the the red one... not realy sure what to do with it right now, if i come up with something i'll probably do another post about it here ;)


{{< figure src="/img/buttons-anim.gif">}}

[^1]: You can find them easily when you search ebay or any other site that sells electronics from china
[^2]: [Sparkfun](https://learn.sparkfun.com/tutorials/transistors/applications-i-switches) describes the basic circuit quite good
[^3]: "super complex"