Newport FPM-8220, Руководство пользователя

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April 2018 27 FPM-8220
Configuring the GPIB Controller
Refer to your computer's GPIB interface documentation for details on how to set it up. These
settings are important:
Primary GPIB Address 1 through 30
Secondary GPIB Address NONE
Timeout 1 second
Serial Port Timeout 1 second
Terminate Read on EOS No
Set EOI with EOS on Writes Yes
Type of Compare on EOS 7-bit
EOS Byte 00h
Please note that overlooking these settings is a common cause of problems.
Changing Operation from Local to Remote
Sending a command over the GPIB or USB bus automatically puts the instrument in remote mode,
which is indicated by the
RMT in the upper right corner of the display. When the instrument is in
remote mode, all front panel controls are disabled except for the RECALL button. Pressing the
RECALL button returns the instrument to local control mode.
Setting the GPIB Address
In local mode, press RECALL and the UP ARROW buttons simultaneously to display the GPIB
address. While the GPIB address is displayed, you can change it to any of 30 addresses from "-
01 -" to "- 30 -" by pressing the
UP ARROW or the DOWN ARROW .
Basic USB concepts
Universal Serial Bus (USB) is a specification to establish communication between devices and a
host controller, which has effectively replaced a variety of earlier interfaces such as serial and
parallel ports. There are three USB standards available, including USB 1.1, USB 2.0, and USB
3.0. Our device is designed to conform to the USB 2.0 standard and USBTMC 488 substandard.
USB cables use 4 lines - Power, Ground and a twisted pair differ/- data lines using NRZI
encoding. The USB connectors are designed so that power and ground are applied before the
signal lines are connected. When the host powers up it performs the enumeration process by
polling each of the Slave devices in turn (using the reserved address 0), assigning each one a
unique address and finding out from each device what its speed is and what type of data
transfer it wishes to perform. The enumeration process also takes place whenever a device is
plugged into an active network. The connectors design along with the process of enumeration
and a lot of host software allows devices to be described as "Plug-and-Play".
When the USB device is enumerated and gets an address from the host, it presents the host
with information about itself in the form of a series of descriptors. The device descriptor tells the
host the vendor and the product ID. The configuration descriptors offer a power consumption