Remote Operation
RS-232 Interface Overview
5
5-23
Table 5-1 summarizes the possible Remote/Local state transitions. (For more
information on IEEE-488 GPIB messages, see “IEEE-488 Overview.”
Table 5-1. Operating State Transitions
From To Front Panel
GPIB
Message
Serial
Command
Local Remote MLA (REN True) REMOTE
Local With Lockout LLO LOCKOUT
Local Go to Local softkey GTL or REN False LOCALRemote
Remote with Lockout LLO LOCKOUT
Local with
Lockout
Local REN False LOCAL
Remote with Lockout MLA (REN True) REMOTE
Local REN False LOCALRemote
with
Lockout
Local with Lockout GTL
5-21. RS-232 Interface Overview
The two Calibrator RS-232 ports are designed in accordance with EIA (Electronic
Industries Association) standard RS-232-C. RS-232 is a serial binary data interchange
operating from 300 to 9600 baud (selectable), and distances up to 50 feet. The Calibrator
rear panel SERIAL 1 FROM HOST port is configured as DTE (Data Terminal
Equipment) while the SERIAL 2 TO UUT is configured as DCE (Data Communications
Equipment). See Appendix C for RS-232 cable and connector information. For detailed
information, see the EIA standard RS-232-C.
A summary of RS-232 terms, interface lines and mnemonics are shown in Table 5-2.
Table 5-2. RS-232 Interface Wiring
Mnemonic Description
CTS Clear to Send
DB-9 Type DB connector, 9 pins
DB-25 Type DB connector, 25 pins
DCD Data Carrier Detect
DCE Data Communications Equipment
DSR Data Set Ready
DTE Data Terminal Equipment
DTR Data Terminal Ready
GND Ground
RI Ring Indicator
RLSD Received Line Signal Detector
RTD Request to Send
RX Receive Line
TX Transmit Line
To Next Page
Loading...
