7) COMM PROMPT (CPRM) , < OFF
- < prompt string >
Defines the 9400A prompt string which may be up to I0 characters
long. The default is OFF. This feature simplifies interactive
programming of the 9400A. When set, the host computer must read the
9400A after every command, even when no response is normally
expected. The 9400A responds either with the prompt string alone or
with its response, followed by the prompt, indicating that it is
ready for another command.
Summary of COMM default values:
COMM HEADER
COMM-TRAILER :
COMM-HELP
COMM-FORMAT
COMM BLOCKSIZE :
COMM-STRDELIM :
COMM-PROMPT
SHORT
CRLF
OFF
GPIB: A format, BYTE
RS232: L format, BYTE, UFIX,COMMA
0
" (Decimal value: 34)
OFF
7.6.8 Status Byte and Mask Register Commands
The 9400A contains a Main Status Byte (STB I) and 5 additional status
bytes, numbered from 2 to 6. Each status byte has an associated mask
register, also numbered from i to 6. The purpose of the status bytes is
to keep track of the internal conditions of the 9400A. The user can use
2 methods of staying informed:
- The status bytes can be read at any time, one by one or in a
single block, with or without simultaneous clearing. This method
ignores all mask registers. The host computer program is required
to continue testing a status bit of interest, e.g., bit #0 of the
OPERATION COMPLETE status byte (STB 5) after the SCREEN_DUMP
command.
-
The user can configure the 9400A to generate an interrupt to the
host computer upon the occurrence of one or several conditions.
The user must demask the bit(s) of the status byte which
corresponds to the condition(s), by setting l’s into the
corresponding bit of the mask in question. In addition, the
corresponding bit in the Main Status Byte (STB I) must also
demasked in order to allow the generation of the Service Request.
This method is much more efficient timewise, but requires a more
complex setup. In addition, the host computer must be configured
to handle an interrupt by the GPIB SRQ-line. See Section 7.11 for
more explanations and examples.
7-34
Remote Operations