Stanford Research Systems DS335, Руководство пользователя

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Programming Commands 3-1
DS335 Synthesized Function Generator
PROGRAMMING THE DS335
The DS335 Function Generator may be remotely programmed via either the
RS232 or GPIB (IEEE-488) interfaces. Any computer supporting either of
these interfaces may be used to program the DS335. Only one interface is
active at a time. All front and rear panel features (except power) may be
controlled.
GPIB Communications The DS335 supports the IEEE-488.1 (1978) interface standard. It also
supports the required common commands of the IEEE-488.2 (1987)
standard. Before attempting to communicate with the DS335 over the GPIB
interface, the DS335's device address must be set. The address is set in the
second line of the GPIB menu (type [SHIFT][1] twice), and may be set
between 0 and 30. The default address is 22.
RS232 Communications The DS335 is configured as a DCE (transmit on pin 3, receive on pin 2) and
supports CTS/DTR hardware handshaking. The CTS signal (pin 5) is an
output indicating that the DS335 is ready, while the DTR signal (pin 20) is an
input that is used to control the DS335's transmitting. If desired, the
handshake pins may be ignored and a simple 3 wire interface (pins 2, 3 and
7) may be used. The RS232 interface baud rate may be set in the second
line of the RS232 menu (type [SHIFT][2] twice). The interface is fixed at 8
data bits, no parity, and 2 stop bits.
Front Panel LEDs To assist in programming, the DS335 has 4 front panel status LEDs. The
RS232 and GPIB LEDs flash whenever a character is received or sent over
the corresponding interface. The ERROR LED flashes when an error has
been detected, such as an illegal command, or an out of range parameter.
The REMOTE LED is lit whenever the DS335 is in a remote state (front panel
locked out).
Data Window To help find program errors, the DS335 has an input data window which
displays the data received over either the GPIB or RS232 interfaces. This
window is activated by typing [SHIFT][2] or [SHIFT][1] three times. The
menu displays the received data in hexadecimal format. The last 256
characters received can be scrolled through using the MODIFY up/down
arrow keys. A decimal point indicates the most recently received character.
Command Syntax Communications with the DS335 use ASCII characters. Commands may be
in either UPPER or lower case and may contain any number of embedded
space characters. A command to the DS335 consists of a four character
command mnemonic, arguments if necessary, and a command terminator.
The terminator may be either a carriage return <cr> or linefeed <lf> on
RS232, or a linefeed <lf> or EOI on GPIB. No command processing occurs
until a command terminator is received. All commands function identically on
GPIB and RS232. Command mnemonics beginning with an asterisk "*" are
IEEE-488.2 (1987) defined common commands. These commands also
function identically on RS232. Commands may require one or more
parameters. Multiple parameters are separated by commas ",".
Multiple commands may be sent on one command line by separating them
by semicolons ";". The difference between sending several commands on
the same line and sending several independent commands is that when a
command line is parsed and executed the entire line is executed before any
other device action proceeds.