Send binary to the serial port

Question

To send a serial string character to the serial port. I would need to call WriteFile(handle, "A", strlen("A"), ...)

However, what if I want to specify and send a hex or binary number? For example, I want to send WriteFile(handle, 0x41, sizeOf(0x41), ...) ?

Is there a function that allow me to do this?

Answer 1

There are many ways.

The most straight forward for you though would be WriteFile( handle, "\x41", 1 ... );

The strlen() is redundant, since you know the length.

Answer 2

If you just want to write one byte, it still needs to be in an array.

So you would need:

int buffer[1024];
buffer[0] = 42;

WriteFile(handle, buffer, 1);

See this: http://msdn.microsoft.com/en-us/library/aa365747(VS.85).aspx