{"id":32463,"date":"2019-10-31T21:47:12","date_gmt":"2019-10-31T18:47:12","guid":{"rendered":"https:\/\/prohoster.info\/blog\/kak-i-zachem-chitat-datashity-esli-mikrokontrollery-vashe-hobbi\/"},"modified":"2019-10-31T21:47:12","modified_gmt":"2019-10-31T18:47:12","slug":"kak-i-zachem-chitat-datashity-esli-mikrokontrollery-vashe-hobbi","status":"publish","type":"post","link":"https:\/\/prohoster.info\/en\/blog\/news\/kak-i-zachem-chitat-datashity-esli-mikrokontrollery-vashe-hobbi","title":{"rendered":"How and why to read datasheets if microcontrollers are your hobby","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

\"How<\/p>\n

<\/p>\n

Microelectronics have become a trendy hobby in recent years thanks to the wonderful Arduino. However, there's a catch: with sufficient interest, one can quickly outgrow DigitalWrite(), but what to do next is not entirely clear. The Arduino developers have made considerable efforts to lower the entry barrier to their ecosystem, yet beyond it lies the dark forest of harsh circuit design, which remains elusive to enthusiasts.<\/p>\n

<\/p>\n

For instance, datasheets. They seem to contain everything you need, just take and use them. But their authors clearly do not aim to popularize microcontrollers; sometimes it seems<\/em>, they deliberately abuse obscure terms and abbreviations when describing simple things to confuse the uninitiated as much as possible. But not everything is so grim; with some effort, the mystery can be unraveled.<\/p>\n

<\/p>\n

In this article, I will share my experiences as a humanities major dealing with datasheets for hobby purposes. The text is intended for those who have moved beyond the basics of Arduino and expect some understanding of how microcontrollers work.<\/p>\n

<\/a><\/noindex><\/p>\n

Let's start with a traditional<\/p>\n

<\/p>\n

Blinking an LED on Arduino<\/h3>\n

<\/p>\n

And here's the code:<\/p>\n

<\/p>\n

void setup() {\nDDRB |= (1<<5);\n}\n\nvoid loop() {\nPINB = (1<<5);\nfor (volatile uint32_t k=0; k<100000; k++);\n}<\/code><\/pre>\n
<\/p>\n
\"What is this?\" \u2013 asks the seasoned reader. \"Why are you writing something to the input register PINB? It's read-only!\" Indeed, the Arduino documentation<\/a><\/noindex>, like many educational articles on the internet, asserts that this register is read-only. I thought so too until I reread the datasheet<\/a><\/noindex> the Atmega328p when preparing this article. And it says:<\/p>\n
<\/p>\n
\"How<\/p>\n
<\/p>\n
This is a relatively new feature; it wasn't available in Atmega8, and not everyone knows about it or mentions it due to backward compatibility concerns. However, it is quite useful for demonstrating that datasheets should be read to utilize all the chip's capabilities, including the lesser-known ones. And this isn't the only reason.<\/p>\n
<\/p>\n
Why else read datasheets<\/h2>\n
<\/p>\n
Typically, Arduino enthusiasts, having played around with LEDs and AnalogWrite, begin connecting various modules and chips to the board for which libraries have already been written. Sooner or later, a library appears that doesn't quite function as intended. At that point, the hobbyist starts tinkering with it to fix the issues, and then...<\/p>\n
<\/p>\n
Something incomprehensible is happening there, which is why I have to go to Google, read numerous tutorials, snag pieces of someone else's suitable code, and finally achieve my goal. This gives a powerful sense of accomplishment, but in reality, the process resembles inventing a bike by reverse-engineering a motorcycle. Moreover, I\u2019m not gaining any understanding of how this bike works. I know this because I\u2019ve been at it for quite a while.<\/p>\n
<\/p>\n
If instead of this fascinating activity, I had spent a couple of days studying the documentation for the Atmega328, I would have saved a huge amount of time. After all, it\u2019s a pretty simple microcontroller.<\/p>\n
<\/p>\n
Thus, reading datasheets is necessary just to have an idea of how the microcontroller is structured and what it can do. And also:<\/p>\n
<\/p>\n