VTI Instruments EX1000A, User Manual

Page: 240 / 320

VTI Instruments Corp.
240 EX10xxA/RX1032/EX1044 Function Calls
vtex10xxA_set_fifo_config
F
UNCTION
P
ROTOTYPE
ViStatus vtex10xxA_set_fifo_config(ViSession vi , ViBoolean report_cjc , ViBoolean report_timestamp ,
ViBoolean report_celsius , ViBoolean blocking_mode );
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.
report_cjc = a Boolean value indicating whether to report the CJC temperatures in the acquisition data. If set to “0”,
CJC temperatures will not be reported, while setting this parameter to “1” enables reporting.
report_timestamp = a Boolean value indicating whether to report delta timestamps per channel in the acquisition
data. When this parameter is set to “1”, timestamp reporting is enabled. When set to “0”, it is disabled.
report_celsius = a Boolean value indicating whether to report the input channel data in units of Celsius (ºC) or
Fahrenheit (ºF). If this parameter is set to “1”, input channel data is reported in °C. If set to “0”, data is reported in
°F
blocking_mode = a Boolean value that indicates whether blocking mode is enabled. When this parameter is set to
“1”, blocking mode is enabled. When set to “0”, blocking mode is disabled.
D
ATA
I
TEM
R
ESET
V
ALUE
report_cjc = 0 report_timestamp = 0
report_celsius = 1 blocking_mode = 0
D
ESCRIPTION
This function sets the data format and overflow behavior of the FIFO memory.
The
report_cjc parameter does not affect the measurement of CJC temperature, but determines if the data will be
displayed. CJC temperatures are measured with every scan, regardless of this setting. Reported CJC temperatures
are always in units of ºC, regardless of the value of the
report_celsius parameter.
The
report_timestamp parameter represents the time, in increments of 100 ns, between the specific channel
measurement and the scan initiation time.
The
blocking_mode parameter sets defines the action taken if the reading buffer fills to its maximum capacity
during scanning. When this mode is enabled, additional readings are discarded leaving the contents of the buffer
intact. With blocking mode disabled, the buffer becomes circular, in that additional readings overwrite the oldest
readings.
NOTE Regardless of the settings of the report_cjc and report_timestamp parameters, the CJC
temperature and delta timestamp information is not accessible through the vtex10xxA_read_fifo
function. They are available through the streaming interface and the parameter settings apply for it.
E
XAMPLE