Measurement Computing Micro 488/EX rev.2.1 - Manual (Page 102)

Section 5 Command Descriptions
5.32
ENTER (Peripheral mode)
In Peripheral mode, the ENTER command receives data from the bus under
control of the Active Controller. The Active Controller must put the Micro488/EX into
the Listen state and configure some bus device to provide the Micro488/EX with data.
The Listen state can be checked with the STATUS 1 command, can cause a reported
event message with the ARM command, or can force a Macro execution with the ON
DOMACRO command. A time-out error will occur (if enabled) if the
Micro488/EX does not receive a data byte within the time out period after issuing the
ENTER
command.
If the character count, count, is specified, then exactly that number of characters
will be read from the device with the serial output terminators appended. Otherwise,
ENTER
terminates reception on detection of the line feed (LF) character, which may be
overridden by specifying the terminator in the ENTER command.
If a terminator, term, option is specified, all CR and LF characters in the input
data are unconditionally discarded. When the specified terminator is detected, it is
discarded and replaced with the serial terminator(s) before being returned to the serial
host. The optional terminator applies ONLY to the ENTER command it is sent with.
The terminator returns to a Line Feed on subsequent ENTER commands.
If the EOI option is specified, all characters are returned to the host until the EOI
line is detected. The character sent with EOI asserted is also returned followed by the
serial output terminator(s).
SYNTAX ENTER[#count|term|EOI|;count|;term|;EOI]
or
EN
[#count|term|EOI|;count|;term|;EOI]
count is the number of characters to ENTER.
term and EOI override the normal IEEE bus input LF terminator.
RESPONSE Device-dependent data. If count is specified, then count characters
will be returned followed by the serial output terminators. Otherwise
the response ends when the IEEE bus input terminator is detected and
the serial output terminators are appended to the returned data.