The sample app is using a thread to read the data in parallel to the main thread as soon as it is reported by the OS. I guess you could use a smaller buffer to get smaller chunks of data. I fail to see the benefit though.

Apart from that you would have to change the way the OS buffers incoming data. I don't know how to do that - or if that's even possible.

Is there any way to get this to real time poll the serial port? I'm using the example, but it seems to be reading big chunks from the buffer at a time.

>to test for NO write
>if (!<some boolean expression>)

Nö, better (readable) is:

if (not <bool expr>)

What does your test look like?

The code reads:

- (BOOL)DTRInputFlowControl
{
return (options->c_cflag & CDTR_IFLOW);
}

I can't see any error here, but it might not return what you think it does. Let me explain.

BOOL is defined as

typedef signed char

YES is defined as

#define YES (BOOL)1

The above method will return 0 (zero) if the CDTR_IFLOW flag is not set and CDTR_IFLOW otherwise (which happens to be 0x00040000). So you may NOT compare to YES.

I.e. instead of

if (<some boolean expression> == YES)

you should write

if (<some boolean expression>)

to test for NO write

if (!<some boolean expression>)

If that doesn't solve your problem, please send me some sample code per mail.

(Small?) bug: the AMSerialPort -(BOOL)DTRInputFlow method always returns NO.