User manual

mentioned on Day 6, you can get around this problem by deleting the old projects. Now you have enough energy again.
You'll find today's programme on the website. Enter your WLAN data and the token code, and already you can upload the programme.
The programme now unites multiple hardware and software actors and buttons. For example, if you push the first button in the app, the LED at
D9 starts to light up. The second
button switches on the LED D3, which is permanently mounted on the board. With the button on the breadboard, you change the status of the
first app LED. You can affect the brightness of the second LED with the potentiometer. Thus you have many different control options for many
different elements.
Day 9: Brightness of the real LED
Behind today's door is another 1-kohm resistor. But today you don't have to change anything in the hardware layout from yesterday. Only a small
detail changes on the interface.
The layout from yesterday
You don't have to re-upload the programme because you're simply manually adjusting the interface from yesterday. If you'd like to load the
interface in the app anyway for safety's sake, you'll find the QR code here as usual. But then you also have to re-enter the token in your
programme.
In order to make the changes manually, you first have to delete the button that was previously responsible for the LED at D9. To do this, tap
briefly on the button while the interface is not started and tap the "delete" option below. There you'll also be shown the energy that you
"recycle." Now, instead of the button, you have to insert a slider. To do this, tap on the plus sign at the top right and select "Slider_L." The slider
appears on the screen. By briefly tapping on the element, you reach its settings. Once you're there, set "Output" to "Digital D9." Note that after
"D9" there's a small red "PWM," a little indication of how today's test works. After these changes, you can start the interface by tapping the Play
button at the top right.
What was previously possible only with the virtual LED is now also possible with real objects. You change the brightness of the LED at D9 by
changing the slider position. Thus, for example, you can build a dimmable living room lamp that can be controlled via app. The keyword for this
subject is PWM (pulse width modulation). Unlike with an incandescent light bulb, for example, you can't simply dim an LED with less voltage.
The procedure here is more complicated and functions by quickly switching the port on and off. The on and off times vary such that it looks like
the LED becomes brighter or darker. The longer the on time is compared to the off time, the brighter the LED appears. The fact that the flickering
of the LED can't be seen or can barely be seen is due to the high speed with which the port is switched. With this procedure, you can also
control engines or generate audio signals.
Day 10: Colour mixing
Behind today's door is the reason for the many 1-kohm resistors. Namely, what you find there is a so-called RGB LED RGB stands for red-green-
blue, since this LED is actually three LEDs that can be connected through a common cathode. By varying the brightness of the individual LEDs
using PWM, you can generate almost every colour conceivable.
You can see the layout of today's circuit in the following figure. Note that the somewhat longer leg (the cathode) must be plugged into the GND
contact strip.
The RGB LED with all three series resistors
In the Blynk app, a totally new element comes into play today, namely the ZeRGBa element (combination of Zebra and RGB). You can already see
roughly how it works from the colourful design. You can either insert the element in your own new project and adjust the pins manually (red at
D3, green at D5 and blue at D6) or load the interface of the test as usual via QR code. Whichever way you choose, don't forget to enter the new
token in the programme, which you can download as usual from the website.
When you have uploaded the programme with your data and the interface has started in the app, you can move the circle in the ZeRGBa widget.
You see that the colour of the circle changes. At the same time, the colour of the RGB LED on the board changes. So you can have fun playing