[misterhouse-users] Initial Compool support, need rs232 help?

[Bill S. <bs...@vi...>]

Hi All,

Attached is the current status of my MH interface to the Compool pool
equipment.  There still is some work to be done, but you can get/set time,
get/set temperature, and get/set equipment states.  There is also _now
versions of the commands where possible.  The test_compool.pl contains some
basic functional testing.

There are a few things that I need to finish (such as supporting some of the
other models than mine, some have different number of aux ports and such).
Also, once I learn perl a bit better, seems this likely should become a
class instead of a package of related functions.

There is one serious problem, however, and I am hoping someone here can
help.  The line that I am pulling the data in from seems very noisy, I get
allot of break_signals and framing_errors reported by the comport.  I see
some data underruns and overruns.  I've parsed the stream to account for
this (the actual data is checksummed so I know if I got it ok).  However, I
am doing this via:

my $data, my $serial_port = $Serial_Ports{Compool}{object};
$serial_port->reset_error;
if ($data = $serial_port->input)
{
   ...
}
$serial_port->reset_error;

This code will run for some period of time (minutes to hours) but eventually
it will hang on the $serial_port->input.  I *think* that internally input is
getting the number of characters expected from the port, and then waiting
for that number.  One of the underflows I see must happen in this case
causing input to never complete.  What can I do here to add some sort of
timeout or better input handling from the port?  The port is 9600/8/n/1 and
I am receiving about 25 characters in a packet (there is usually 2.5 seconds
between packets unless a user manually activates something via a physical
controller).  So I timeout of (max) 100ms from the last character received
should be plenty, anyway to do this?

Bill