Serial comm differences between PC & Mac?

[Sarah Reichelt]

> IIRC, it looks like 3 bugs:
>
> Char read commands come up short on XP for reading 256 chars.
> Multi-char read commands throw away data after LF on OS X.
> Codes 10, 11 and 12 are garbled in reading uint1 on OS X.
> Multi-uint1 read commands sometimes come up short on OS X based on 
> garbage at end (?).
> uint1 read commands input garbage if the data is not there.
>
>
>> Fortunately, since the phone system only uses a certain set of chars, 
>> I
>> can filter out all of the junk, & make this work for my needs. BTW, 
>> I'm
>> using both the keyspan usa-28 & usa-28x on OSX, & com1 on the PC. The
>> results are the same with either keyspan adapter.
>
> It looks like you might get garbage if you try to read a uint1 and 
> none is there.  The time might come when one of the garbage bytes 
> looks like a valid letter.
>
> It might be that my short data for 256 char reads does not apply to 
> single char reads.
>
> There are several reported bugs for serial on OS X; you will have to 
> work around those.
>
> Windows serial I/O is blocking (up to 2 seconds) and OS X serial I/O 
> is not (except for a weird OS X feature in opening the modem where a 3 
> second delay is forced).
>
> I think someone (Sarah?) has reported better luck with usa-28 than 
> with usa-19.
>
> I suspect that Rev is not setting some terminal parameters on ports, 
> leaving them as they are, on OS X.
>
I use the Keyspan USA28X without any problems, but I have never tried 
any other Keyspans. My current favourite adapter is a very simple & 
cheap device called an EasySync USB to RS232 converter. I only use Mac 
OS X but it comes with drivers for Windows as well.

With regard to the original poster's serial problems, do you get the 
same results on the PC using the Keyspan and plugging the serial 
connector in directly?

Cheers,
Sarah