VTI Instruments EX1629, User Manual

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EX1629 Command Set 283
vtex1629_set_shunt_value
F
UNCTION
P
ROTOTYPE
ViStatus vtex1629_set_shunt_value (ViSession vi , ViInt32 _VI_FAR channels[] ,ViInt32 numberOfChannels ,
ViInt32 shuntSource , ViReal64 shuntValue );
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.
channels = an input integer array containing a list of channel numbers for which the shunt value will be set. Valid
input values: 0 to 47.
numberOfChannels = the size of the channels list. Valid input values: 1 to 48.
shuntSource = a integer input value indicating the shunt source for which the value is to be set. Valid input values:
0 to 4.
shuntValue = a real input value that defines the value of the specified shunt.
D
ATA
I
TEM
R
ESET
V
ALUE
shuntValue (source 0, 1, 4) = 0.00000
D
ESCRIPTION
This function sets the value of a shunt resistor based on a given channel and shunt source. The following values are
allowed for the
shuntSource parameter:
Decimal
Value
Hex
Value
#define Symbol shuntSource Description
0 0x00 VTEX1629_FRONT_PANEL_REMOTE Front panel remote
1 0x01 VTEX1629_FRONT_PANEL_LOCAL Front panel local
2 0x02 VTEX1629_INTERNAL_REMOTE Internal remote
3 0x03 VTEX1629_INTERNAL_REMOTE Internal local
4 0x04 VTEX1629_TEDS_REMOTE TEDS remote
Local and Remote refer to how the shunt resistor is connected to the bridge. For “Local”, the connection is made
within the EX1629. For “Remote”, the connection is made externally, using the ±RCal signals.
Front Panel, Internal, and TEDS, refer to the three types of shunt sources supported. “Front Panel” refers to the
shunt resistors that may be connected directly to the front panel of the EX1629, which are shared by 16 channels
(0 through 15, 16 through 31, and 32 through 47). Only one channel may be connected to the Front Panel shunt at a
time. “Internal” refers to the internal, per-channel shunt resistor. Since each channel has its own, all channels may be
shunted simultaneously. “TEDS” refers to a special shunt resistor/TEDS (1-Wire) configuration. Only one channel
may be shunted via the TEDS shunt at a time.
While the internal shunt sources are valid function parameters, their values are provided from the calibration file and
are not user alterable.
E
XAMPLE
ViSession instrumentHandle;
ViStatus status;
ViInt32 channels[] = {0,1,2,3};
…
status = vtex1629_set_shunt_value(instrumentHandle,
channels,
4,
SHUNT_SOURCE_FPS_LOCAL,
50000.0);