VXi VT1422A Manual De Usuario

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136 Programming the VT1422A for Data Acquisition and Control  
Below is an example command sequence for Figure 4-8. It assumes that the 
FIFO mode was set to BLOCK and that at least one algorithm is sending 
values to the FIFO.
following loop reads number of values in FIFO while algorithms executing
loop while "measuring" bit is true
see STAT:OPER:COND bit 4
SENS:DATA:FIFO:COUNT? 
query for count of values in 
FIFO
input n_values here
if n_values >= 16384
Sets the minimum block size to 
transfer
SENS:DATA:FIFO:PART? n_values
ask for n_values
input read_data here
Format depends on FORMat cmd
end if
end while loop 
following checks for values remaining in FIFO after "measuring" false
SENS:DATA:FIFO:COUNT?
query for values still in FIFO
input n_values here
if n_values
if any values...
SENS:DATA:FIFO:PART? n_values
input read_data here 
get remaining values from FIFO
end if
Begin Data Retrieval
Exit Data Retrieval
Algorithm Stopped?
Any Values in FIFO?
Enough Values
in FIFO?
Execute Final Transfer
Command
Execute Bulk Transfer
Command
DATA:FIFO:COUNT?
DATA:FIFO:PART? <n_values>
no
no
no
yes
yes
yes
STAT:OPER:COND?
(bit 4 "measuring")
Figure 4-8. Controlling Reading Count