User`s guide

Overview
DAQFactory can communicate with a wide variety of devices with serial (RS-
232/422/485) and Ethernet connections. This guide explains how to start
communicating with your device and how to create a protocol to interpret the
language your device speaks. Since serial and Ethernet communications are done
almost identically, we’ll simply refer to it as serial communications. Ethernet is
actually a serial technique, meaning bits of data are sent over the wire one after
another. There are additional layers with Ethernet handled by your operating
system and your hardware, but as far as DAQFactory is concerned, Ethernet, RS-
232, RS-422 and RS-485 are pretty much identical. This allows you to apply any
protocol to either serial or Ethernet ports.
DAQFactory handles serial communications by splitting the transport layer: RS-
232, RS-422, RS-485, Ethernet, etc, from the protocol used on that layer: Modbus,
DF1, NMEA. In less technical speak you can think of the transport layer as a
telephone. There are many different types of telephones: ones that plug into a
wall, cordless phones, cellular phones, and even VOIP. We then communicate on
the phone. The protocol is the language that we speak: English, Swahili, Klingon,
modem speak. By splitting the telephone from the language, we can use any
language on any phone type. DAQFactory provides all the tools for communicate
over the various phone types. DAQFactory provides several different languages to
communicate with common devices, but also provides the tools for you to specify
your own special languages. In order for you to communicate with your device,
you have to select and configure the proper telephone type, and you have to
speak the proper language over the phone.
This guide assumes you have a basic knowledge of DAQFactory and have at least
progressed through the guided tour in the user’s guide. If you are going to create
your own protocol, we suggest reviewing the section on sequence scripting in the
user’s guide as well. We assume a basic knowledge of DAQFactory scripting in
our discussion of user protocols.
This guide applies to DAQFactory 5.34 or newer.
USB:
It should be noted now, though, that USB devices, even though the S stands for
Serial, are not handled by Windows the same way as Ethernet or normal RS232
serial communications. USB devices require very specialized software to allow for
plug and play. The manufacturer of your USB device should provide you with a
driver to help you communicate with the USB device. For some devices, such as
mice and flash drives, this driver is included with Windows. For others, the
manufacturer will provide a driver which will make your USB device appear like a
Window’s resource. The most common examples of this are serial to USB
converters. These devices include a driver which makes the USB device appear
like a standard Windows serial RS232 comm port. Since it appears as a comm
port, you should ignore the USB device and just pretend you have an extra comm