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EX10xxA Web Page Operation

The

Input State

status section displays the measured digital level (0 or 1) of the VTB channels each

time the page is accessed or refreshed. The information does not update automatically on an input
level transition or on a timer. Consequently, it should only be used to monitor static or slowly
changing levels. The input monitoring functionality operates regardless of the state of the

Output

Enable

control.

The

Output State

control provides a pull-down selection in which the output level of each VTB

channel is specified. This setting represents the level that the channel will assume if/when enabled
as an output. When a channel is not enabled, this selection has no effect.

The

Output Enable

control enables each VTB channel as an output. Once enabled, a channel will

assume the level specified in the

Output State

control. When not enabled as an output, a channel

becomes tri-stated.

NOTE

Before specifying a VTB channel as an output, ensure that no other active voltage drivers are
connected to the channel. Otherwise, incorrect operation or instrument damage could result.

The

Pulse

control is used to generate a single-shot 1 µs pulse. The specific operation of the pulse

depends on the static level programmed for that channel. When a channel is programmed with a
static level of high, the pulse will be low-going. When a channel is programmed with a static level
of low, the pulse will be high-going. Each pulse generation requires a separate command. This
control is only valid when the channel is enabled as an output. Normally, pulse operation is used
once a channel’s static output level is already defined. However, if selections are applied together
to change the output state and output a pulse, the channel will first assume the new output state and
then output the appropriate pulse.

IMITS

ENU

The Limits menu is used to configure the limit condition evaluation system of the EX10xxA.

Limits

This entry page is used to specify the values for the two programmable limit sets. These limits,
termed limit set 0 and limit set 1, are programmable on a per channel basis. Only one set of limits
is displayed at a time on the page. Navigation between the sets is provided by the

Set

control, a pull-

down selection.

By default, the values in limit set 0 are set automatically, based on the EU conversion and units
selection for each channel. Specifically, the upper and lower limit values are set to the upper and
lower values of the EX10xxA measurement range, as specified in Table 3-2. For example, if input
channel 0 is configured for an E type conversion and a units selection of ºC, its upper and lower
limit values will be +900 and -200, respectively. To override the automatic setting and set the values
manually, check the

Manual

checkbox and enter new values. Values can be entered in decimal or

scientific notation, but will always be displayed in scientific notation. Limit set 1 operates in manual
mode only.

NOTE

Limit sets operating in manual mode do not automatically adjust for changes in EU conversion or
units selection. For proper operation, limit values should be set after EU conversion and units
selections are made and reset upon subsequent configuration changes.

DIO Limit Events

This entry page is used to link one or multiple limit conditions to the operation of a channel on the
digital I/O port. Nominally, the results of limit set 0 evaluations are represented in the front panel
LEDs, and the results of both limit set evaluations are accessible through the instrument driver. The
DIO limit event mechanism offers the additional ability to precisely control a DIO channel through
the limit evaluations on one or more input channels.