When writing through a serial connection to arduino from any programming (processing etc.), arduino reads its values as bytes correct? On the programming side, if I write the number one as a string, what is that in terms of the byte value verses its integer value in arduino? What does arduino read strings as? Say if I write the value one through the serial connection.
Thanks!
Say if I write the value one through the serial connection.
Are you writing values in binary or as strings (ASCII data)?
On the programming side, if I write the number one as a string, what is that in terms of the byte value verses its integer value in arduino?
Serial.read() will return '1' (or 49 or 0x31). If you subract '0' (or 48 or 0x30) from that value, you will get the numeric value of 1.
I never see any references to stream.parseInt().
I have intentionally coded my serial data to use only integers so when i send the data, currently over serial monitor but ultimately through some form of RF, I simply look for my SOP, Look at the next character to determne where it is coming from since the serial in will ultimately come from potentially 4 different sources and then use parseInt to grab all of the integer data.
So if I send a data stream of <B,100,100,1,1,2300,400,5,4,3653> to the Arduino, I don’t have to do any kind of crazy subtract ‘0’ low byte, high byte, &= translations to get my integers, I just get integers. Since my received data after that initial letter will always be the same number of items, I could even throw a string or other character data in there and handle it in code. For example,
<B,100,100,1,1,2300,400,5,4,3653,Wade>
Once I saw the < and looked at the first letter ‘B’, I know exactly what the format of this stream of data is so I can parseInt for 9 steps and then read the character data. Using a module like the CC1101 from TI handles the error checking issues so I won’t have to worry about that potential problem either since I think checksum would be a little more difficult to manage using this method.
Since I can send a 1 or a 0, this obviously works for boolean data as well.
So PaulS, is there something I should know that would steer me away from this or do you avoid it because it limits the data input to int’s? I just find it so much easier to use. I ask because I have recently seen two of your posts where you reference the exact same code chunk to read serial and I learned a lot from it on how to start and end the read etc but for now am sticking to the parseInt method.
The Stream::parseInt() function is new in 1.0. My code works for any version of the IDE.
Ah!
Since I am new this is the only version I know.
I was starting to worry that it might not be the best method.