VTI Instruments EX1629, Руководство пользователя

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VTI Instruments Corp.
242 EX1629 Command Set
vtex1629_set_conf_scanlist
F
UNCTION
P
ROTOTYPE
ViStatus vtex1629_set_conf_scanlist (ViSession vi , ViInt32 _VI_FAR confElements[] ,ViInt32
numConfElements );
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.
confElements = an integer input array indicating which confidence data elements will be measured. Valid input
values: 0 to 12.
numConfElements = the size of the confElements list. Valid input values: 0 to 12.
D
ATA
I
TEM
R
ESET
V
ALUE
confElements = None
D
ESCRIPTION
This function sets the list of confidence data elements that will be measured and returned along with the main bridge
data. The confidence data elements are the following:
Decimal
Value
Hex
Value
#define Symbol confElements Description
0 0x00 VTEX1629_CONFSRC_BRIDGE_POS Bridge (+)
1 0x01 VTEX1629_CONFSRC_BRIDGE_COMM Bridge (common mode)
2 0x02 VTEX1629_CONFSRC_BRIDGE_NEG Bridge (-)
3 0x03 VTEX1629_CONFSRC_EXCITE_POS Excite (+)
4 0x04 VTEX1629_CONFSRC_EXCITE_NEG Excite (-)
5 0x05 VTEX1629_CONFSRC_EXCITE_NEG_SENSE Excite Sense (-)
6 0x06 VTEX1629_CONFSRC_EXCITE_POS_SENSE Excite Sense (+)
7 0x07 VTEX1629_CONFSRC_EXCITE_POS_CURR Excite Current (+)
8 0x08 VTEX1629_CONFSRC_EXCITE_NEG_CURR Excite Current (-)
9 0x09 VTEX1629_CONFSRC_POS_CAL Calibration Bus (+)
10 0x0A VTEX1629_CONFSRC_NEG_CAL Calibration Bus (-)
11 0x0B VTEX1629_CONFSRC_GND Ground
12 0x0C VTEX1629_CONFSRC_EXCITEOUT_BUFF Excite Out (Buffered)
NOTES 1) Confidence elements 9 through 11 are for system diagnostic use only and should not be
employed during normal operation.
2) Confidence element 12 can only be used on EX1629 with firmware version 1.0 or later.
In order to clear the confidence scan list, a value of 0 should be set for the numConfElements parameter. In this
case, the value of the confElements parameter is arbitrary.
NOTE The confidence data is filtered by a transfer function represented by the following differential
equation: y(n) = 0.01x(n) + 0.99y(n-1), where y(n) is the filtered confidence data and x(n) is the
measured confidence data. This function serves to reduce noise variance.
E
XAMPLE
ViSession instrumentHandle;
ViStatus status;
ViInt32 confchannels[] = {3, 4, 5, 6};
ViInt32 numberOfChannels = 4;
…
status = vtex1629_set_conf_scanlist (instrumentHandle,
confchannels,
numberOfChannels);