I am using the LabVIEW library to try and embed Digilent Discovery 2 O-scope into a custom instrument and try to have it programatically record a pulse from a pulse train the instrument is generating.
For the most part I've been able to set up the range of my reading, trigger levels, trigger parameters, how much data to read and at what rate. What I can't seem to do is arm the o-scope, set "Auto Trigger to False" and have the time out be longer than 0.5 seconds in a straight forward way. The LabVIEW help for the MSO Run vi says that the time out is set by a combination of "trigger delay" and "the greater of pretrigger time*2, or 0.5 seconds". I don't want any information before the trigger, so I set "pretrigger time" to zero (otherwise it records for that amount of time before my trigger). Setting a non-zero value for "trigger delay" seems to do dual duty of not only setting a time to read in seconds after the trigger is detected, but also as the timeout for MSO Run to timeout if it hasn't gotten a trigger. Is there a way to independently set these two parameters? It seems very silly to have one parameter function as both settings.
The pulse I am trying to record is variable but is in the time range of 6ms. I would like to arm the o-scope well before I expect the pulse to happen and then just record the pulse. I can't program "trigger delay" to say 2 seconds (essentially setting my timeout for MSO Run for 2 seconds) and then have the o-scope record 2 seconds after it detects the trigger because by then, the pulse is long gone. I can't seem to untie these two parameters OR find a way to strictly set MSO Run vi timeout without programming a "trigger delay". Ideally I want the "trigger delay" to be 0 seconds and to program the MSO Run timeout time to however many seconds I want or until I programmatically stop looking for a trigger. Can anyone help?
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JFLO
I am using the LabVIEW library to try and embed Digilent Discovery 2 O-scope into a custom instrument and try to have it programatically record a pulse from a pulse train the instrument is generating.
For the most part I've been able to set up the range of my reading, trigger levels, trigger parameters, how much data to read and at what rate. What I can't seem to do is arm the o-scope, set "Auto Trigger to False" and have the time out be longer than 0.5 seconds in a straight forward way. The LabVIEW help for the MSO Run vi says that the time out is set by a combination of "trigger delay" and "the greater of pretrigger time*2, or 0.5 seconds". I don't want any information before the trigger, so I set "pretrigger time" to zero (otherwise it records for that amount of time before my trigger). Setting a non-zero value for "trigger delay" seems to do dual duty of not only setting a time to read in seconds after the trigger is detected, but also as the timeout for MSO Run to timeout if it hasn't gotten a trigger. Is there a way to independently set these two parameters? It seems very silly to have one parameter function as both settings.
The pulse I am trying to record is variable but is in the time range of 6ms. I would like to arm the o-scope well before I expect the pulse to happen and then just record the pulse. I can't program "trigger delay" to say 2 seconds (essentially setting my timeout for MSO Run for 2 seconds) and then have the o-scope record 2 seconds after it detects the trigger because by then, the pulse is long gone. I can't seem to untie these two parameters OR find a way to strictly set MSO Run vi timeout without programming a "trigger delay". Ideally I want the "trigger delay" to be 0 seconds and to program the MSO Run timeout time to however many seconds I want or until I programmatically stop looking for a trigger. Can anyone help?
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