Omega Model CYD211 User’s Manual
Remote Operation
4-1
CHAPTER 4
REMOTE OPERATION
4.0 GENERAL
The Model CYD211 is equipped with an RS-232C serial computer
interface. The interface allows computer automation of instrument setup
and temperature measurement data collection. Nearly every feature of the
instrument can be accessed through the computer interface. Interface
capabilities including setup information and example programs are provided
in Paragraph 4.1. Interface commands including a command summary are
described in Paragraph 4.2.
4.1
SERIAL INTERFACE OVERVIEW
The serial interface used in the Model CYD211 is commonly referred to as
an RS-232C interface. RS-232C is a standard of the Electronics Industries
Association (EIA) that describes one of the most common interfaces
between computers and electronic equipment. The RS-232C standard is
quite flexible and allows many different configurations. However, any two
devices claiming RS-232C compatibility cannot necessarily be plugged
together without interface setup. The remainder of this paragraph briefly
describes the key features of a serial interface that are supported by the
instrument. A customer supplied computer with similarly configured
interface port is required to enable communication.
4.1.1 Physical
Connection
The Model CYD211 has a 9 pin D-Subminiature plug on the rear panel for
serial communication. The original RS-232C standard specifies 25 pins but
both 9- and 25-pin connectors are commonly used in the computer industry.
Many third party cables exist for connecting the instrument to computers
with either 9- or 25-pin connectors. Paragraph 5.6 gives the most common
pin assignments for 9- and 25-pin connectors. Please note that not all pins
or functions are supported by the Model CYD211.
The instrument serial connector is the plug half of a mating pair and must
be matched with a socket on the cable. If a cable has the correct wiring
configuration but also has a plug end, a “gender changer” can be used to
mate two plug ends together.