C compile errors: stray '\200' in program and expected ')' before numeric constant

Question

I copied this program and am having trouble with the void downFrequency function (I think). This is for Arduino Uno. Here are the compiler errors: Compiling \'MY_dds\' for

Answer 1

Simple copy always mess up the source code.

One can check the "stray" problem via cat -A yoursrc.c

To me, I usually reformat the code by vim in two steps.

vim yoursrc.c
:%!tr -cd '[:print:]\n'

Then compile gcc yoursrc.c

Answer 2

You've somehow ended up with "en dash" characters, rather than normal minus signs, in the downFrequency function.

Make sure you're editing using a text editor, not a word processor; and for each of these:

toFrequency = (toFrequency – 1);
                           ^

delete the marked character, and retype as a normal minus sign.

(If you're interested in the gory details, the "dash" character is Unicode 2013, encoded in UTF-8 as three bytes with octal values 324,200,223, which is why you see those numbers in the error messages.)

Answer 3

The compiler is complaining that there are non-ASCII characters in your source file.

My octal fu is rusty, but it looks like UTF-8 to me. 342 200 223 is E2 80 93 which is Unicode "EN DASH." This code was given a minus sign makeover by a text editor with a degree in cosmetolegy.

Answer 4

Probably your double quote symbols (") were wrong. Please check if they are actually ", and not ” .