Measurement Computing Micro 488/EX rev.2.1 - Manual (Page 79)

Section 5 Command Descriptions
5.9
@
The system command @, followed by a CR and/or LF, is used to unlock the
Micro488/EX from an inappropriate command. An example of such a command would
be requesting data from a nonexistent device with time outs disabled. It is not
recommended for use but is provide in the Micro488/EX for upward compatability
with other IOtech serial to IEEE controllers. Timeouts are a better method of signaling
bus faults.
When the @ command is received, the serial handshake line (RTS) is un-asserted.
It is asserted when the Micro488/EX is capable of buffering commands. If XON/XOFF
handshake is selected, the software handshake state is not modified.
Issuing the @ command installs the power-on formats for DATE, DAY, TIME and
CASE and software programmable terminators are returned to the power-on conditions.
Macro and log buffer data is not effected. If a macro has been defined as the
STARTUP
, it will execute. It also is equivalent to issuing the following commands…
DISARM MASK OFF
ERROR OFF REQUEST 0 (with *SRQ)
ID;@ TIME OUT 0
LOG OFF TRACE OFF
The @ character, referred to as the 'ID' character, can be changed or disabled by
using the ID command. If it is anticipated that the ID character may be part of the
data
within an OUTPUT or SEND command, it should be disabled. It is also
recommended that the ID character not be involked within a macro.
SYNTAX @
RESPONSE None
MODE Any
BUS STATES None
EXAMPLE PRINT #1,"@"