C-Bus thermostat to AC (Coolmaster) using 5500PACA with RS232

This code is from the main post here

Based on Darren example. If anyone feels he could help to optimize it, please do. I tried use ELSE, it did not work, so I had to use IF's all the time. Maybe some feedback could be added, but I could not make any, being not a programmer myself.

This controls:
1 AC addressed 001
with the thermostat Communication Group 3
through COM1 of 5500PACA device

Once in Cool mode - thermostat controls the AC.
Once in Heat mode - thermostat controls only heating device using internal logic and relays, does not control AC until we allow it to. Group "heat on" turns AC control in Heat mode on.
AC goes to Heat mode with another module, which is not here (because you have to turn all AC's to Heat, you cannot do just one).

Code:

{ global variables }
s3 : string;
LastSetPoint3 : real;
LastOnOff3 : real;
m3 : string;

{ Initialisation }
OpenSerial(1, 1, 9600, 8, 1, 0, 0);
LastOnOff3 := 0;
LastSetPoint3 := 0;

{ module code }
{room 3 - cond 01 ON/OFF}
if (GetIntIBSystemIO("HVAC Operating Type", 3, HVACZoneU) <> LastOnOff3) then
begin
if (GetIntIBSystemIO("HVAC Operating Type", 3, HVACZoneU) = 0)
then
begin
  format(m3, 'off 001', #13);
  WriteSerial(1, m3);
  LastOnOff3 := GetIntIBSystemIO("HVAC Operating Type", 3, HVACZoneU);
end
end;

{room 3 - cond 01 cool}
if (GetIntIBSystemIO("HVAC Operating Type", 3, HVACZoneU) <> LastOnOff3) then
begin
  if (GetIntIBSystemIO("HVAC Operating Type", 3, HVACZoneU) = 2)
then
begin
  format(m3, 'on 001', #13);
  WriteSerial(1, m3);
  LastOnOff3 := GetIntIBSystemIO("HVAC Operating Type", 3, HVACZoneU);
end
end;

{room 3 - cond 01 HEAT if "heat on" is on}
if (GetIntIBSystemIO("HVAC Operating Type", 3, HVACZoneU) <> LastOnOff3) then
begin
if (GetIntIBSystemIO("HVAC Operating Type", 3, HVACZoneU) = 1) and (GetLightingState("heat on") = ON)
then
begin
  format(m3, 'on 001', #13);
  WriteSerial(1, m3);
  LastOnOff3 := GetIntIBSystemIO("HVAC Operating Type", 3, HVACZoneU);
end
end;

{room 3 setpoint send to AC}
  if (GetRealIBSystemIO("HVAC Set-Level", 3, HVACZoneU) <> LastSetPoint3) then
begin
  format(s3, 'temp 001 ',GetRealIBSystemIO("HVAC Set-Level", 3, HVACZoneU):0, #13);
  WriteSerial(1, s3);
  LastSetPoint3 := GetRealIBSystemIO("HVAC Set-Level", 3, HVACZoneU);
end;
{room 3 end}

 

This Part
format(m3, 'off 001', #13);
WriteSerial(1, m3);

Can be replaced by declaring it as a string constant

m3 = 'off 001'#13;

and how dose this module run as there are quite a few if statements which will put a lot of traffic on c bus every scan

 

Thank you!
It runs ok, because "if (GetIntIBSystemIO("HVAC Operating Type", 3, HVACZoneU) <> LastOnOff3)" makes it almost identical to ONCE, I guess.

I tried to make less IF's, more ONCE's, but it stops working