Hello! The Internet of Things (IoT) is already heard by every grandparents. In the flock, greenhouse or garage, for sure, there is already a smart socket. Let's get down to business. It is necessary to know the humidity and temperature, but for some reason the display is not possible to use.
List of reasons:
- expensive;
- afraid of moisture;
- laziness to solder;
- small print that you can’t see at all;
- grandmother is concerned about the aesthetics inside the greenhouse, and she also values minimalism;
- all listed together.
In this case, there is an excellent reason to use the color approach to displaying information. Everything would be fine, but the primary colors are completely worthless - some seven (from the rainbow). Can you distinguish between blue and blue or yellow from orange? If you can, then grandmother is unlikely. What to do? Remove such weird colors! Leave: Red, Yellow, Green, Blue, Pheasant Violet and White (unexpectedly, yes?). How much did it work? 6. And there are 10 digits, and even a minus for negative numbers, a floating point and a separator. We will be smart and make a flasher! Violet - it will be 5, and six it will be 5 + 1, and 1 will be Red. Just fit. Huh! Table 1 shows the colors for the corresponding characters.
Table 1
| Digit (or symbol) | Colour |
|---|---|
| Zero | flashing violet |
| One | RED on |
| Two | burns YELLOW |
| Three | burns GREEN |
| Four | burns BLUE |
| Five | LIGHT PURPLE |
| Six | flashing PURPLE / RED |
| Seven | flashing PURPLE / YELLOW |
| Eight | flashing PURPLE / GREEN |
| Nine | Flashing PURPLE / BLUE |
| Minus (-) | blinking WHITE / RED |
| Dot (.) | blinking WHITE |
| End of line (\ n) | burns WHITE |
In order to display the number, it is necessary, of course, to download and connect the library. Then declare the user callback function void callback (int, int, int) R, G, B - channels (from 0 to 255), which will access the hardware (light the LED). Call the lightf function, where the first argument will be a pointer to this same callback function, then a line with a format that is completely analogous to printf and any number of arguments. Remember to use the newline character \ n after each qualifier in the format string.
At my fingertips lies the M5Stack FIRE Base Unit with built-in Neopixel panels, for testing, as nothing is better. A video demonstrating a sketch displaying the Pi number up to 6 decimal places can be seen here .
I didn’t just say that IoT at the very beginning. Seriously, this approach is perfect for displaying a PIN code for pairing devices, etc.
Love and do not forget your old people. Thanks for attention!
Link to the library here