User`s manual

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EX7000-OEM Introduction 11
Each driver board has a single programmable delay parameter. The programmable delay for any
board should be set to the maximum value required by any component connected to that board.
Data is latched to the gate of the FET dictating whether or not the FET will sink current and
energize the relay coil. There is an optionally populated pull-up resistor from the FET drain to
+5 V for connection to devices which require TTL control. This is detailed in the section below.
Each relay section can support identification of one relay if the relay has ID bits (optional on some
types of relays) and the IDs are tied to the communications bus and the main interface board will
report the data back to the application code. If indicator contacts are present, the status of the relay
will also be reported back.
INTERFACING WITH OTHER COMPONENTS
The EX7000-OEM is capable of controlling other programmable components, such as filters and
attenuators, through either the high-current channels or the 32-bit parallel I/O. Consecutive
channels can be grouped and allocated to a particular component and assigned a logical name
which can be used in application code or through the graphical interactive utility.
Additionally, optional versions of the EX7000-OEM are available to convert the 72 drive lines
such that they are capable of driving TTL inputs. Options are available for 24, 48, or 72 TTL
capable drive lines. This is in addition to the 32-bit parallel I/O bus.
Channels are grouped and assigned to a logical name through the an intuitive graphical utility. As
an example, eight consecutive channels on a driver board can provide the logic that controls an
8-bit attenuator. The command to set the attenuator is called as follows:
driver->Attenuator->Item[0].Data = 16;
<writes the value of 16 to the first attenuator in the list>
FEATURES
Relay Odometer
Each relay drive line has an associated “odometer” which tracks the number of times a relay coil
has been actuated. This data is written to non-volatile memory and can be called from application
code or the web interface. This assists preventative maintenance programs as relays can be closely
monitored as they near end-of-life.
Exclude Lists
The supplied API supports the implementation of exclude lists. Undesirable combinations of relay
closures can be stored and warnings or errors will be generated any time an excluded combination
is attempted. This helps prevent unsafe conditions such as shorting sources to ground or coupling
one source to another.
Scan Lists
Up to 16,000 scan list elements can be stored to help reduce overhead that can be accrued when
relying on the host controller to manage the sequencing of switch states. A predefined list of
switch states can be stored on-board and advanced through hardware control/handshaking with
external system devices via the LXI Trigger Bus or the GP digital I/O port. Use of scan lists can
considerably speed up test execution times.