Specifications

Appendix C - Glossary of Terms RS-422 And RS-485 Applications Ebook
Page 106 of 137 Manual Documentation Number: <DocNumber>
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Driver Control
In a two-wire RS-485 system, the transmit driver must be enabled to transmit
and disabled to receive. (See RTS Control and SD Control)
Drivers
Hardware drivers provide current or voltages to other hardware devices.
The line driver in a RS-485 system is a transmitter that provides voltage
and current drive to the receiving devices on the RS-485 network.
Software drivers provide a standard software interface for a computer
Operating System such as Windows, MacOS, UNIX, Linux, SunOS or Solaris.
DSR
Data Set Ready. A RS-232 serial port line which is held high (+3 volts or more)
when the data set (DCE device) is turned on and available. This is one of the
handshaking lines. A device wanting to communicate with the device (or
modem) may check the status of this line to determine if the device is
available.
DTE
Data Terminal Equipment. A device that originates data for transmission, such
as a computer or serial terminal. The RS-232 DTE or DCE designation
determines whether a signal is a input or a output. A DTE device outputs a
transmit signal to the transmit input on a DCE device. Although designations
are the same, the functions of the signals are reversed between DTE and DCE.
DTR
Data Terminal Ready. An RS-232 serial port line which is held high (+3 volts or
more) when the terminal is turned on and available. This is one of the
handshaking lines. A device wanting to communicate with the terminal may
check the status of this line to determine if the device is available.