To configure scheduled communications with an I/O
Device, you need to flag it as a "Scheduled" device. This is done
using the Express Communications Wizard. If
your I/O Device is not capable of scheduled communications, the
scheduling options will not be presented by the wizard.
Note: Scheduled communications will not
work for drivers that are designed to handle Report-By-Exception
protocols. For communicating with your I/O Device outside of
schedule use the IODeviceControl function.
To schedule communications with an I/O
Select the Project Editor (or
press the Project Editor icon).
Choose Communication | Express Wizard or
open Citect Explorer.
Double-click the Express I/O Device Setup icon in the Communications
folder of the current project.
Follow the instructions to work
through the screens, selecting the relevant I/O Device, and so on.
When the scheduling screen displays, check the Connect I/O Device to PSTN box, even if your I/O Device
is not connected via a modem (but leave the Phone number to dial
and Caller ID fields blank).
Fill out the schedule fields to
achieve the desired schedule. For example (all based on a Synchronize at time of 10:00:00).
If you enter 12:00:00 in the Repeat every field, and start your project at 9 a.m.,
the I/O Server will communicate with the I/O Device at 10 a.m.,
then once every 12 hours after that, i.e. 10 p.m., then again at 10
a.m. of the following day, etc.
If you enter 12:00:00, and start
your project at 4 p.m., the I/O Server will communicate with the
I/O Server at 10 p.m., then again at 10 a.m. of the following day,
etc. i.e. it will assume that communications were established at 10
a.m., so it continues as if they had been, communicating once every
12 hours after 10 a.m.
If you enter 3 days, and start
your project at 9 a.m. on a Wednesday, the I/O Server will
communicate with the I/O Device at 10 a.m., then once every 3 days
after that, i.e. 10 a.m. on the following Saturday, then at 10 a.m.
on the following Tuesday, etc.
If you enter the 6th of December
in the Repeat every, and start your project
during November, the I/O Server will communicate with the I/O
Device at 10 a.m. on December 6, then again on December 6 of the
following year, and so on.
Startup for a persistent connection. To disconnect a persistent
connection, you need to call the IODeviceControl() function with
If your I/O Device is not
connected via a modem, you need to go to the Ports form (select
Ports from the Communication menu) and change the Port number to
the actual number of the COM port.