FreeBSD and controlling an alarm via relay

Achilleas Mantzios achill at
Tue Jul 5 14:30:13 UTC 2011

Στις Tuesday 05 July 2011 16:10:59 γράψατε:
> On Mon, 4 Jul 2011, Achilleas Mantzios wrote:
> [snip]
> > I was thinking of some relay board (instead of the old modem), 
> > possibly ethernet controlled
> This box has relays and GPIO available via ethernet. It's probably 
> overkill for your application, but it's well made and easy to use:

That is too big for my application, thanx anyway.
Most probably i'll go for something cheaper like this one

Could i use the ucom driver to talk to the USB device like a normal serial device, via /dev/cua*** ?
The above link says one needs to talk to the relay with:
8 Data, 1 Stop, No Parity,Baud rate : 9600
and the commands look like:
FF 01 00 (HEX) 
255 1 0 (DEC)

could i be able to specify those over ucom? 
do you know any application, perl library, utility or just a guide for standard C serial port programming?

i have used mgetty/vgetty in the past to control some modems.
I do not know if there any fancier methods to access the serial port, but this is how i used to do it, back in 7.*
/usr/local/bin/vm shell -l cuad1 -S
where reads like:
use Modem::Vgetty;

my $v = new Modem::Vgetty;


if i could speak directly with e.g. "255 1 0" like
$v->send("255 1 0");
that would be awesome...
i guess i will have to try it out.
> I'd also look at manufactureres such as Moxa and LANtronics.

Achilleas Mantzios

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