User`s guide

154
Chapter 4 Features and Functions
Totalizer Operations
• Using the hardware jumper labeled “Totalize Threshold” on the
module, you can control the threshold at which an edge is detected.
Move the jumper to the “AC” position to detect changes through 0
volts. Move the jumper to the “TTL” position (factory setting) to
detect changes through TTL threshold levels.
The maximum count is 67,108,863 (2
26
-1). The count rolls over to “0”
after reaching the maximum allowed value.
• You can configure the totalizer to reset its count after it is read
without losing any counts (TOTalize:TYPE RRESet command).
Then, if the totalizer is included in a scan list, the count will be reset
on every scan sweep. The count is also reset whenever it is read
directly by pressing from the front panel or when sending the
SENSe:TOTalize:DATA? command.
• You can configure the instrument to generate an alarm when a
specific count is reached on a totalizer channel. These channels do not
have to be part of the scan list to generate an alarm. Alarms are
evaluated continuously as soon as you enable them. For more
information, see “Using Alarms With the Multifunction Module” on
page 148.
• You can monitor a totalizer channel even if the channel is not part of
the scan list (the internal DMM is not required either). The count on
a totalizer channel is not reset when it is being monitored (the
Monitor ignores the totalizer reset mode).
• A Factory Reset (*RST command), Instrument Preset
(SYSTem:PRESet command), and Card Reset (SYSTem:CPON
command) reset the count to “0”.
2.5 V Threshold (TTL)
0 V Threshold (AC)
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