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Remote/Local Operation
At power-on the instrument will be in the local state so the REM indicator is not displayed on the
Status Line. In this state all front panel operations are possible. When the instrument receives a
command from an interface the remote state will be entered and the REM indicator is displayed on
Status Line. In this state the front panel is locked out and remote commands only will be processed.
The instrument may be returned to the local state by pressing the LOCAL key; however, the effect
of this action will only remain until the instrument receives another character from the interface,
when the remote state will once again be entered. Returning to Local by this action will keep the
settings at their last remotely set values.
USB Interface
The USB interface is a virtual COM port which can be controlled by a PC as if it was an RS232
device. The instrument is supplied with a CD containing an .inf file for the standard Microsoft
drivers available in Windows 2000, XP, Vista and Windows 7; the installation wizard will install the
driver (32-bit or 64-bit) appropriate to the PC’s operating system. Any updates are available via the
TTi website, http://www.aimtti.com/support.
Installation of the interface driver is achieved by connecting the instrument to a PC via a standard
USB cable. The Windows’ plug and play functions should automatically recognise the addition of
new hardware attached to the USB interface and, if this is the first time the connection has been
made, prompt for the location of a suitable driver. Provided that the standard Windows prompts are
followed correctly Windows will install the appropriate driver and establish a virtual COM port within
the PC. The number of the new COM port will depend upon the number of co-existing COM ports
within the PC. The virtual COM port can be driven by Windows applications in exactly the same way
as a standard COM port, except that the Baud rate setting of the virtual COM port is ignored.
The driver will remain installed on the PC so that the establishment of a virtual COM port is done
automatically each time the instrument is connected to the PC via USB in the future.
Further virtual COM ports are created for each additional instrument connected to the PC via USB.
Each instrument is assigned a separate virtual COM port when it is first connected and the same
COM port will be assigned each time that instrument is subsequently connected; the PC software
makes use of the unique code embedded in each instrument to link it to the same virtual COM port
irrespective of which physical USB port it is connected to.
Use can also be made of the ADDRESS? command to easily identify which instrument is being
controlled by a particular COM port. Although the addressing capability is ignored in USB operation
the address can still be set and used as an identifier; set each USB-connected instrument to a
different address and send the ADDRESS? command from each virtual COM port to confirm which
instrument is connected to that port.
LAN Interface
The LAN interface is designed to comply with the LXI Core 2011 and contains the interfaces and
protocols described below. Since it is possible to misconfigure the LAN interface, making it
impossible to communicate with the instrument over LAN, a LAN Configuration Initialise (LCI)
mechanism is provided via the menus from the front panel to reset the instrument's interfaces to the
factory default. The default setting is for the instrument to attempt to obtain settings via DHCP if
available or, if DHCP times out (30 seconds), via Auto-IP. In the very unlikely event that an Auto-IP
address cannot be found a static IP address of 192.168.0.100 is assigned. Resetting the LAN
removes any password protection which has been set on the wab page.
To reset the LAN interface press the
LanRst
soft-key on the Utility-
I/O
menu.
For more information on LXI standards refer to
www.lxistandard.org
