Instructions

Page 64
9 USB Connections | File System & Files Types
9.1.1 Understanding USB Connections
The instrument has two USB ports only one of which may be used at a time. The required port
is accessed by a sliding shutter which ensures that only the exposed port can be used.
The Type A port presents a USB host interface which will accept flash drives conforming to the
USB Mass Storage Class (MSC). Drives with capacities from 32MB to 32GB are supported.
USB Hard Disk Drives are not supported and this port is not compatible with any other class of
device including the HUB class.
If any unsupported device type is connected a message will be displayed to alert the user.
NOTE: Certain small capacity USB flash drives have been seen that try to connect as a hub
before exposing the MSC device. This type of flash drive is not compatible and cannot be used
with this instrument.
When a compatible flash drive is connected to the instrument there will be no activity until the
Setup/Functions > System/File Ops > File Ops control screen is called up, then the Disk light
will flash and the Switch Drive key will become active. This key will allow access to the files
stored on the flash drive. The Copy key in the File Actions control screen will also become
available. See section 9.1.2 “Using an External Flash Drive” for more information on reading
and writing the flash drive.
The Mini B port is for connection to a PC and has two possible uses, each will cause the
instrument to expose a different device type to the PC. When the instrument is powered on the
Mini B port is inoperative and the PC, if connected, will not be able to 'see' the instrument. The
correct device type will be exposed when the user performs an appropriate action. The two
types of device that the instrument can expose are Mass Storage Class (MSC) and
Communications Device Class (CDC). These classes and their uses are discussed in the
following paragraphs.
The PSA will expose the MSC when the user executes Setup/Functions > System/File Ops >
File Ops and then chooses the Link to PC option from the File Ops control screen. See section
9.1.3 “Linking to a PC via USB” for more information.
The instrument will expose the CDC when the user executes Setup/Functions > System/File
Ops > System Utilities followed by Status/System > Screen > View on PC. This function is only
available with Option U02 enabled. For more information see 17 Appendix A “View on PC”.
It should be noted that CDC is used only for screen data exchange when View on PC is
selected. It is not possible to transfer file data while in this mode. To exchange files between
instrument and PC requires MSC and in this mode View on PC is not available.
The user can, however, switch freely between these modes by executing the key sequences
above but connection to the View on PC application will be lost when Link to PC is selected.
9.1.2 Using an External Flash Drive
The USB Type A connector on the left hand side of the instrument is arranged as USB Host
and is intended exclusively for the connection of a USB Flash Drive. This enables files to be
copied to and from the internal memory of the instrument. Note that files cannot be loaded from
or saved to external memory directly.
Copy operations are performed using the File Ops (File Operations) function - see section 5.6.
The instrument pre-defines a folder system for the USB Flash Drive whereby different file types
are placed in specific folders. These folders are automatically created when the File Ops
function is selected with a Flash Drive plugged in.
A master folder is created called PSA within which are sub-folders named TRACES, IMAGES,
SETUPS, LOGS, and TABLES. Files copied from the instrument onto the external drive are
automatically placed into the correct folder. However, where files are being placed onto the
external drive from a personal computer, they must be put into the correct folder or it will not be
possible to copy them onto the instrument.