VXi VT1422A 사용자 설명서

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VT1422A Command Reference   253
ALGorithm
ALGorithm:UPDate:CHANnel
ALGorithm:UPDate:CHANnel <dig_chan
This command is used to update 
variables, algorithms, ALG:SCAN:RATIO, and ALG:STATE changes when the 
specified digital input level changes state. When the ALG:UPD:CHAN command is 
executed, the current state of the digital input specified is saved. The update will be 
performed at the next update phase (UPDATE in Figure 7-1) following the channel's 
change of digital state. This command is useful to synchronize multiple VT1422As 
when all variable updates are to be processed at the same time.
Parameters
Comments
The duration of the level change to the designated bit or channel MUST be at 
least the length of time between scan triggers. Variable and algorithm changes 
can be accepted during the INPUT or UPDATE phases (Figure 7-1) when INIT 
is active. All writes to variables and algorithms occur to their buffered elements 
upon receipt. However, these changes do not take effect until the ALG:UPD:CHAN 
command is processed at the beginning of the UPDATE phase. Note that the 
ALG:UPD:WINDow command specifies the maximum number of updates to 
do. If no update command is pending when entering the UPDATE phase, then 
this time is dedicated to receiving more changes from the system.
Note
As soon as the ALG:UPD:CHAN command is received, the VT1422A begins to 
closely monitor the state of the update channel and cannot execute other commands 
until the update channel changes state to complete the update
Note that an update command issued after the start of the UPDATE phase will 
be buffered but not executed until the beginning of the next INPUT phase. 
At that time, the current stored state of the specified digital channel is saved and 
used as the basis for comparison for state change. If at the beginning of the scan 
trigger the digital input state had changed, then at the beginning of the UPDATE 
phase the update command would detect a change from the previous scan trigger 
and the update process would begin.
When Accepted: Before and After INIT.
Send with VXIplug&play Function: hpe1422_cmd(...)
Parameter
Name
Parameter
Type
Range of
Values
Default 
Units
dig_chan
Algorithm 
Language channel 
specifier (string)
Input channel for VT1533A: Iccc.Bb
for VT1534A: Iccc
where ccc=normal channel number and
b=bit number (include ".B")
none