VTI Instruments EX1629, Руководство пользователя

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VTI Instruments Corp.
140 EX1629 Command Set
vtex1629_get_confidence_limit
F
UNCTION
P
ROTOTYPE
ViStatus vtex1629_get_confidence_limit (ViSession vi , ViInt32 channel , ViInt32 confSrcEnum, ViPReal64 min ,
ViPReal64 max );
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.
channel = an integer input value indicating the channel for which the completion resistor is desired. Valid input
values: 0 to 47.
min = the returned minimum confidence limit value.
max = the returned maximum confidence limit value.
confSrcEnum = defines the confidence source value that will be queried. Valid input values: 0 to 12.
D
ATA
I
TEM
R
ESET
V
ALUE
Not applicable to this function.
D
ESCRIPTION
This function queries and retrieves the minimum and maximum values for confidence data limit checking.
Confidence limit checking mode is only valid for main bridge sampling frequencies less than 1 kHz. Returned
values in the datapage correspond to the confidence channels for channels in the active scanlist. There exists a
confidence limit check result summary field (shown in the diagram below) which indicates if any of the limits on all
active confidence sources for a particular channel were exceeded or not. This is a 16-bit field, stored in the least-
significant 16 bits of a UINT32 variable.
0 = Confidence Data within Limits
1 = Confidence Data Limit
exceeded for CH 15
0 = Confidence Data
within Limits
1 = Confidence Data
Limit exceeded for CH 0
31 0 15
MSW
(Unused)
LSW
(Confidence Limit exceeded status)
Confidence Limit Check Result summary (Available per Analog Board)
A detailed confidence limit check result (shown in the diagram below) is also available which returns two bits per
channel per confidence source – that is, MAX Limit Exceeded and MIN Limit Exceeded, per channel, per
confidence source. There is one UINT32 entry per bridge channel in the bridge scanlist. This UINT32 has two bits
per confidence source (CONF_NUM_SRC sources per bridge channel), one to represent MAX limit exceeded and
one to represent MIN limit exceeded. The MSW (lower CONF_NUM_SRC of the upper 16-bits) represent the MAX
Limit Exceeded status for each of the CONF_NUM_SRC confidence sources, and the LSW (lower
CONF_NUM_SRC bits of the lower 16-bits) represent the MIN Limit Exceeded status for each of the
CONF_NUM_SRC confidence sources. Bit 0 represents the MIN Limit Exceeded status for source 0. Bit 16
represents the MAX Limit Exceeded status for source 0. Bit (CONF_NUM_SRC-1) represents the MIN Limit
Exceeded status for source (CONF_NUM_SRC-1). Bit (16+CONF_NUM_SRC-1) represents the MAX Limit
Exceeded status for source CONF_NUM_SRC. The rest of the sources follow the same pattern.