Arduino i2c example write register how to#
Arduino i2c example write register serial#
Arduino i2c example write register code#

The libraries are usually written by advanced users, so it's not so hard to understand with some background like knowing the datasheet for used MCUs and so on.I am programming the MAX77651 in I2c using the FT4222 device.

Arduino i2c example write register code#

For me is most difficult to read the code without indentation or even worst with bad indentation, bad variable names. But for the begginers without good knowlege of C++ it's hard anyway. This is not explicitly mentioned in that tutorial, but both are used here. If you want binary, you have to use 0b00010111. 4) In C++ numbers starting by zero are in Octal base.If you can't read the value (for example it's internal address like for eeproms) you have to have this value in memory anyways. If you don't have register value, you have to Read & Modify & Write it back.

How? For in memory variable just use bit masking. 2) If you look for 'Bit manipulation' then there are loads of Tutorials.1) The & is used for bit masking in this case.4.: Are all covered by Bit Manipulation tutorial on AVRFreaks forum Tutorials. It's not that I am smarter (or better) than them, I just don't understand why somebody would write a complex code when there is no(really) need for that.

Arduino i2c example write register serial#

Should Arduino library be written in a way that others could find it difficult to figure out the idea behind it? In other words, to figure out what the developer was exactly doing? I remember that one person used a lot of messy code to read something from sensor and then formula to convert it from binary-coded decimal to print it to Serial Monitor, while the same thing could be done with simply So, how did somebody come with this equation?

BUT, where is this equation from? I searched (obviously wrong) as much as I could, but there was nothing about it. However, when doing this conversion: 17/10*16 + 17%10 it writes correct number 17. You get different number, 13 or 10 (can't recall what number, I know it was wrong). But when you do this: Wire.beginTransmission(module_address) Let's say, that you have a timer and you wish to set 17 seconds for countdown to 0.And to do that, you need to write number 17 to register one, but number should be binary-coded decimal.

Arduino i2c example write register how to#

How to write flag without affecting option 2 and option 3? Or in other words, how to write to register 3's write flag? If I take 11000000 could affect because maybe I do not know what exactly option 2 and 3 do, or I do not wish to interfere with default setup.Ĭertain modules have to be written in binary-coded decimal. Imagine that hypothetical module has third register in write mode looking like this:ĭata Byte3 | write flag.| option2.|.option3. Why the previous problem isn't written anywhere? So many tutorials, so many books, but I 'discovered' it by accident when I tried to figure out how one library was working. What does this '&' after Wire.read() REALLY means? (I know that it points to option within register, but I do not really understand this, why is it there) To read only option 3, I would use this code: Wire.beginTransmission(module_address) īyte readings = Wire.read() & 0x1F //0x1F is hexadecimal of binary 0001111 for option 3 in register 1 For example, lets say that imaginary module has First read register like this:ĪDDRESS | BIT 7 | BIT 6 | BIT 5 | BIT 4 | BIT 3 | BIT 2 | BIT 1 | BIT 0ĭata Byte1 | mute. Usually, every register has more than one 'option' inside. So far, working with ANY module I got, it was NEVER that easy. Wire.write(something) //write to second register Wire.write(something) //Write to first register When it comes to writing, it's even worse: Wire.beginTransmission(Module_Address) //Use this to start transmission To read Wire.requestFrom(Module_Address, 3) //Read three registers Call me stupid, but I have the feeling like somebody told me that 1 + 1 = 2, and then gave me some polynomial equation to solve :(Īll book examples and almost all tutorials look like this imaginary example: Wire.beginTransmission(Module_Address) //Use this to start transmission I've read few books and too many tutorials, but I could summarise these in two:Ī) all tutorials are just showing the very basics of how to use these methods and b) they don't actually explain the steps, like everything is totally self explanatory. Being novice, I almost never use libraries that are already written by somebody, I try to create my class for module in order to truly understand how this module works and to learn how to manipulate with it. I Googled this a lot, and it seems that I am not the only one having problems with really understanding Wire.write() and Wire.read().