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SECTION 6.0
IEEE-488.2 INTERFACE
6.1
INTRODUCTION
The Instruments For Industry, Inc. (IFI) Amplifiers can be operated remotely from a computer
having IEEE-488 (GPIB), RS-232, USB or ETHERNET. These interfaces will allow the
amplifier to be remotely controlled by sending commands to the amplifier. Additionally, the
amplifier status and forward and reverse power readings may be read over the remote.
6.2
IEEE-488.2 INTERFACE
The IFI Amplifiers have the IEEE-488.2, General Purpose Interface Bus (GPIB) interface. All
amplifier functions can be controlled by coded messages sent over the interface bus via the
24-pin socket connector on the rear panel of the unit. IEEE-488.2 Standard is implemented,
which defines the protocols and syntax of commands. The GPIB command codes for the IFI
Amplifier series are discussed on subsequent pages and, for ease of identification; the
command codes are identified within the text by bold capital characters. For full information
on the IEEE protocols and syntax, the IEEE-488.2 Standard should be consulted.
6.2.1 GPIB Address
Each amplifier has a unique GPIB address that allows communication to the amplifier on a
multi-bus interface (like GPIB). The GPIB address of the amplifier is set by via the Front
panel using the Control knob at the start up menu. Select an address that is different than the
addresses of any other instruments on the GPIB bus.
6.2.2 Using National Instruments’ GPIB Controllers
In order for the amplifiers to operate correctly with a National Instruments GPIB controller
card, the following must be done: (Items 1-5 are done in the IBCONF program.)
1.
Set "Terminate reads on
EOS
" to
yes
.
2.
Set "Set
EOI
with
EOS
on Writes" to
yes
.
3.
Set the
EOS
byte to
0Ah
(an ASCII line feed character).
4.
Set "Send
EOI
at end of writes" to
yes
.
5.
Set "Enable
repeat addressing
" to
yes
at the board level.
6.
When sending command strings to the amplifier, a carriage return character (
0Dh
)
followed by a line feed character (
0Ah
), must always be appended to the command,
