F.W. Bell 7030, Инструкция по эксплуатации

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F.W. BELL Model 7030 Gauss/Tesla Meter Instruction Manual
Section 7 – Remote Operation 7-41
INTERMIXING
“COMMON” AND
SCPI COMMANDS As mentioned earlier a string sent to the instrument can contain more than
one command as long as the commands are separated by semicolons(;).
“Common” and SCPI commands can be intermixed.
MESSAGE
TERMINATORS When transmitting a string to the instrument the message must be
“terminated” properly to notify the instrument that the message is
complete. One way is to append an ASCII line feed (LF) character as the
final character in the string, which is a 0A hex or 00001010 binary. Note
that 0A hex is equivalent to 10 decimal, but sending the two ASCII
characters “10” will not work. It must be the single byte representation of
the LF control character.
If using the IEEE-488 bus the second way to terminate a message is to
assert the End-or-Identify (EOI) bus line at the same time the final
character is sent to the instrument. It is also acceptable to send the LF
character and assert EOI with that character. In most cases sending the
LF character and/or asserting the EOI line is a function of the IEEE-488
controller card being used, and can be specified when the card’s
configuration program is run. Usually the user has the option to
automatically append the LF character and/or assert the EOI line with
every transmission to the instrument. If not it is the programmer’s task to
append the LF character to each string and/or make sure the EOI line is
asserted with the last character transmitted.
When using the RS-232 port the instrument will always send the LF
character every time it transmits a message to the system controller.
When using the IEEE-488 bus the instrument will send the LF character
and assert the EOI line every time it transmits a message to the system
controller.