VTI Instruments EX1629, Руководство пользователя

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EX1629 Command Set 175
vtex1629_get_pattern_trig_configuration
F
UNCTION
P
ROTOTYPE
ViStatus vtex1629_get_pattern_trig_configuration (ViSession vi , ViInt16 _VI_FAR lxiTrigLines[] ,ViInt16
_VI_FAR dioLines[] , ViPBoolean timer , ViPInt32 lxiOutput , ViPInt32 lxiInput );
F
UNCTION
P
ARAMETERS
vi = contains a session handle to the instrument. This handle is obtained by the function and remains valid until the
session is closed.
lxiTrigLines[] = an integer input array specifying 1) the LXI Trigger Bus channels that will be configured to
“listen” for TRIG events and 2) the polarity of the incoming signal will cause the EX1629 to trigger. Valid return
values: 0 to 255.
dioLines = an integer input array specifying 1) the digital I/O channels that will be configured for trigger events,
and 2) the polarity of the incoming signal will cause the EX1629 to trigger. Valid return values: 0 to 255.
timer = a Boolean input value that indicates whether the EX1629 will generate trigger events based on the internal
timer. When this parameter is VI_TRUE(1), periodic trigger events will be generated. Valid return values:
VI_FALSE(0) or VI_TRUE(1).
lxiOutput = this parameter specifies which LXI Trigger Bus line will be used to output the trigger event signals.
Valid return values: VTEX1629_LXI_LINE_ZERO to VTEX1629_LXI_LINE_SEVEN.
lxiInput = this parameter specifies which LXI Trigger Bus line will be used to input trigger event signals. Valid
return values: VTEX1629_LXI_LINE_ZERO to VTEX1629_LXI_LINE_SEVEN.
D
ATA
I
TEM
R
ESET
V
ALUE
Not applicable to this function.
D
ESCRIPTION
This queries and returns the EX1629’s current configuration for the pattern trigger mode of operation. This mode
allows the EX1629 to accept TRIG events from multiple sources. While in pattern mode, the instrument can accept
TRIG events from the LXI Trigger Bus, digital I/O bus, internal timer, and the software trigger function. The re is
no need to explicitly enable the software trigger source. It is always available for use while in pattern trigger mode.
All of the conditions specified must be met for a trigger event to be generated. If multiple conditions are specified
for the same LXI or DIO line, any of the conditions for that line can be met to satisfy the trigger pattern
requirements for that line.
The
lxiTrigLines[] parameter is an array of four elements with each array element being an unsigned 8-bit integer.
Each bit of this integer corresponds to an LXI Trigger Bus channel. Specifically, the least significant bit corresponds
to LXI Trigger Bus channel zero and the most significant bit corresponds to LXI Trigger Bus channel seven. Each
element specifies which events the EX1629 will accept for trigger events on the LXI Trigger Bus for different clock
edges or states. If a user wants to specify a channel for trigger events, the corresponding bit should be set to “1”. The
individual array elements specify the following:
0 = lxiTrigLines (Positive Edge)
1 = lxiTrigLines (Negative Edge)
2 = lxiTrigLines (Positive Level) 3 = lxiTrigLines (Negative Level)
For example, if a user wishes to trigger the EX1629 on a negative edge signal coming into the LXI Trigger Bus on
channel 0 and a positive level on channels 3 and 6, then:
lxiTrigLines[1] = 0000 0001 = 1 (0x01) and
lxiTrigLines[2] = 0100 1000 = 72 (0x48).