Programming the VT1422A for Data Acquisition and Control 139Chapter 4
To enable ALG1 and ALG2 and disable ALG3 and ALG4:
ALG:STATE ’ALG1’,ON enable algorithm ALG1
ALG:STATE ’ALG2’,ON enable algorithm ALG2
ALG:STATE ’ALG3’,OFF disable algorithm ALG3
ALG:STATE ’ALG4’,OFF disable algorithm ALG4
ALG:UPDATE changes take effect at next
update phase
VXIplug&play Users: See the function hpe1422_cmd to send ALG:STATE.

Setting Algorithm

Execution

Frequency

The ALGorithm:SCAN:RATio ’<alg_name>’,<num_trigs> command sets
the number of trigger events that must occur before the next execution of
algorithm <alg_name>. To execute ’ALG3’ only every twenty triggers, an
ALG:SCAN:RATIO ’ALG3’,20 command can be sent followed by an
ALG:UPDATE command. ’ALG3’ would then execute on the first trigger
after INIT, then the 21st, then the 41st, etc. This can be useful to adjust the
response time of a control algorithm relative to others. The *RST default for
all algorithms is to execute on every trigger event.
Example SCPI Command Sequence
This example SCPI command sequence puts together all of the steps
discussed so far in this chapter.
*RST Reset the module
Setting up Signal Conditioning (only for programmable SCPs & RSCUs)
INPUT:FILTER:FREQUENCY 2,(@116:119) On-board SCP channels
INPUT:FILTER:FREQUENCY 10,(@14000:14931) 128 Remote RSCU channels
INPUT:GAIN 64,(@116:119)
INPUT:GAIN 8,(@120:123)
set up digital channel characteristics
INPUT:POLARITY NORM,(@125) (*RST default)
OUTPUT:POLARITY NORM,(@124) (*RST default)
OUTPUT:TYPE ACTIVE,(@124)
link channels to EU conversions (measurement functions)
SENSE:FUNCTION:VOLTAGE AUTO,(@100:107) (*RST default)
SENSE:REFERENCE THER,5000,AUTO,(@108)
SENSE:FUNCTION:TEMPERATURE TC,T,AUTO,(@109:123)
SENSE:REFERENCE:CHANNELS (@108),(@109:123)
configure digital output channel for "alarm channel"
SOURCE:FUNCTION:CONDITION (@132)
execute On-board channel calibration (can take several minutes)
*CAL?
enter statement here for cal return
execute Remote channel calibration on RSCUs
CAL:REMOTE? (@14000:14931)
enter statement here for cal return
Direct data acquisition channels placed in Scan List. On-board channels 00-07
and 128 remote channels covered by VT1539A SCPs in positions 5 & 6
ROUTE:SEQUENCE:DEFINE (@100:107,14000:14931)
Configure the Trigger System
ARM:SOURCE IMMEDIATE (*RST default)
TRIGGER:COUNT 1 (*RST default)
TRIGGER:TIMER .010 (*RST default)