Specifications

4-6 Remote Programming
DS360 Ultra Low Distortion Function Generator
Command Format
Communication with the DS360 uses ASCII characters. Commands may be in either
UPPER or lower case. A command to the DS360 consists of a four character command
mnemonic with an optional ?, arguments if necessary and a command terminator. The
terminator must be a linefeed <lf> or carriage return <cr> on RS232, or a linefeed <lf> or
EOI on GPIB. No command processing occurs until a terminator is received. Commands
function identically on RS232 and GPIB whenever possible. Command mnemonics
beginning with an asterisk (*) are IEEE-488.2 (1987) defined common commands. These
also function identically on RS232. Commands may require one or more parameters.
Multiple parameters are separated by a comma (,). Multiple commands may be sent on
the same line by separating them with semicolons (;).
There is no need to wait between commands. The DS360 has a 256 character buffer and
processes commands in the order received. If the buffer fills, the DS360 will hold off
handshaking on the GPIB and attempt to hold off handshaking on RS232. Similarly the
DS360 has a 256 character output buffer to store output until the host computer is ready
to receive it. If either buffer overflows, both buffers are cleared and an error is reported.
The present value of a particular parameter may be determined by querying the DS360
for its value. A query is formed by spending a question mark (?) with the command
mnemonic and omitting the desired parameter from the command. Values returned from
the DS360 are sent as a string of ASCII characters terminated with a carriage return <cr>
on RS232 and by a linefeed <lf> on GPIB. If multiple query commands are sent on one
command line (separated by semicolons), the answers will be sent individually, each with
a terminator.
Examples of Commands:
FREQ 1000 <lf> Set the Output Frequency to 1.0 kHz
*TRG <lf> Trigger a sweep or burst
FUNC? <lf> Query the output function.
Interface Ready and Status
The No Command bit in the Serial Poll Status Byte signals that the DS360 is ready to
receive and execute commands. When a command is received, this bit is cleared,
indicating that command execution is in process. No other commands will be processed
until this command is complete. Commands received during this time are stored in the
buffer to be processed later. Only GPIB serial polling will generate a response while a
command is in progress. When all pending commands have executed, the No Command
bit is set again. By checking the No Command bit, a host computer can ensure that all
previously sent commands have finished before sending a new command.
Since most commands execute very quickly, the host computer does not need to
continually check the No Command bit. Commands can be sent one after another and
they will process immediately. However some commands, such as self tests, may require
a long time to execute. In addition, the host computer may need to check that these
commands executed without error. In these cases, the status should be queried.