If you are ever confused about the size of a particular data type, you can use sizeOf( data type) function to get the size.

Data TypeĪs you can see, most of these are more than one byte so sending them over I2C will be a bit of a problem. What you have to do is split the number into individual bytes, put them into an array, and send it over. On the other end, you read the array in as individual bytes and rebuild it into the appropriately sized number. To do this, we will be using a few things you might not have come across before. The datatype byte is pretty much the same as char and uint_8 and as you would imagine, it stores a single byte. The & and | characters are used for bitwise addition. Finally, we will also be using > which shifts bits to the right. Then we declare an array of type byte with two elements I will have full examples down at the bottom, but I want to quickly go over an example for sending 16 bit numbers.įirst we declare an integer and assign it a value The finally thing is that I will use the hex number 0xFF, which is the same as binary 11111111 because it is shorter. We need to set the first element to the first byte of bigNum and the second element to the second byte of bigNum.

We get the second element by anding it with 0xFF (11111111), which essentially just isolates the last byte. We get the first element by shifting bigNum 8 bits to the right and anding it with 0xFF.

Arduino wire library choose bus