VISA resource error

[yangyang-rexxar]

Hi all,

I have a vi to operate Agilent 34405A DMM.

The vi is called by TestStand sequence,it always work fine.

Suddenly it show me an error such as "Insufficient system resources to perform necessary memory allocation,-1078807800"

Then I restart my PC and DMM, It works well again.

I want to know why?

[Makoto]

The error code -1078807800 (= 0xBFB2B308) is not found in VISA error codes, therefore it might be from IVI driver or TestStand.  Do you call Close VI for the Agilent instrument driver when you have finished to use the DMM?  The Open and Close call for the instrument driver must be done for the same number of times.  Forgetting to call Close VI may cause memory or resource leak problem.

[yangyang-rexxar]

Thanks verymuch Makoto

Please check my VI and give some advice.

In my flow,I have turn on and turn off section.

[yangyang-rexxar]

The Global vi is here.

[Makoto]

I saw the VIs you attached. (Sorry but I could not run them because of different IO environment.)

The VIs seem like include some power-supply control routines using IviDCPwr class driver and direct GPIB Write.  And I found that the VIs - "Power Supply ON or OFF" send GPIB commands for the supply.  Is the power supply that appeared in the "Power Supply ON or OFF" and "Current Consumption Test 1.01" the same instrument?  If so, you should control VOLTAGE/CURRENT/OUTPUT of the power supply through the IviDCPwr using Configure Voltage Level, Configure Current Limit, and Configure Output Enabled VIs, because your code already has IVI dependent parts in "Current Consumption Test 1.01".

Also, what is the relationship between the VIs you attached and Agilent 34405 DMM?  If you want to measure the consumption current values by DMM, you should use IviDmm class driver instead of IviDCPwr.  If using IviDCPwr for measurement processing, it means that you measure the current or voltage by using power supply's embedded measurement functions.

[yangyang-rexxar]

Hi Makoto

Your are right! The 3 VIs are work in a TestStand sequence, the step is on,measure and off for a same instrument.

Follow your advice, I will change GPIB write to Configure Voltage Level, Configure Current Limit, and Configure Output Enabled VIs

I measure current by using power supply's embedded measurement functions.

Any misgivings?

What method dose "IviDmm" measure current? Not supply's function?

[Makoto]

> What method dose "IviDmm" measure current? Not supply's function?

IviDmm Read VI performs a measurement then acquires the data.  Before using the IviDmm Read VI, you should change the DMM to "ammeter mode" by using IviDmm Configure Measurement VI. The Read VI just queries the default measurement item configured before.

Mind that the IviDmm class driver can only be used with a DMM instrument such as 34405, 34410, or old 34401A.  Normally an IVI driver for DC power supply provides IviDCPwr class interface but does not provide IviDmm, even if the instrument equips an embedded measurement function.  Therefore you can't use any functions of IviDmm class interface with your DC power supply.

Your existing approach - using IviDCPwr Measure VI - is right if you measure with the power supply's embeded function.

このメッセージは　09-19-2006 06:22 PMに Makoto が編集しています。