CG635 Remote Programming
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CG635 Synthesized Clock Generator
CG635 Remote Programming
Introduction
The CG635 may be remotely programmed via the standard GPIB interface or the RS-232
serial interface. Any host computer interfaced to the CG635 can easily control and
monitor the operation of the CG635.
GPIB
The CG635 comes with an IEEE 488 standard port for communicating over GPIB. The
port is located on the rear panel of the CG635.
This interface is enabled via the front panel by pressing the keys ‘SHIFT’, ‘GPIB’, ‘Hz’.
The primary GPIB address of the instrument is also set via the front panel by pressing the
keys ‘SHIFT’, ‘ADDRS’, MODIFY
Ÿ
or
ź
, ‘Hz’. Valid GPIB addresses range from 0
to 30. Enabling the GPIB interface causes the RS-232 interface to be disabled. The GPIB
LED in the INTERFACE section of the front panel will be on when GPIB is the
selected interface.
The factory default GPIB address is 23.
RS-232
The CG635 comes standard with an RS-232 communications port. The port is located on
the rear panel of the CG635.
The RS-232 interface connector is a standard 9 pin, type D, female connector configured
as a DCE (transmit on pin 3, receive on pin 2). The communication parameters are fixed
at: 9600 Baud rate, 8 Data bits, 1 Stop bit, No Parity, RTS/CTS Hardware Flow Control.
This interface is enabled via the front panel by pressing the keys ‘SHIFT’, ‘RS-232’,
‘Hz’. Enabling the RS-232 interface causes the GPIB interface to be disabled. The
RS-232 LED in the INTERFACE section of the front panel will be on when RS-232 is
the selected interface.
Front-Panel Indicators
To assist in programming, the CG635 has four front panel indicators located under the
INTERFACE section: RS-232, GPIB, ACT, and ERR. The RS-232 LED is on when the
CG635 is configured to accept commands over RS-232. The GPIB LED is on when the
CG635 is configured to accept commands over GPIB. The ACT LED serves as an
activity indicator that flashes every time a character is received or transmitted over one of
the remote interfaces. The ERR LED will flash when a remote command fails to execute
due to illegal syntax or invalid parameters.