How can I get information of the switched channel in an example program from NI?

[bigmatzeman]

When I use the example program "niSwitch DMM Switch Synchronous Scanning.vi", I'am not able to get any information, wich channel is active. Wich block has to be used and how must I connect it to see this.

The other one is, that te sytax for the scan list, described in the help does not switch through the channel, how has this to be modified?

Im using a SCXI 1128 in Slot 8 of a 1052 combo chassis and the DMM is a PXI 4070 in the Slot 2.

[Norbert_B]

Bigmatzeman,

The example you are pointing to can be run with two restrictions:
1st) The DMM has to be in the rightmost slot of the PXI part of the chassis (Slot 4 in 1052)
2nd) You have to set the trigger of the Switch to "TTL0" and the MC-trigger of the DMM to "LBR_TRIG0"

I checked that with a 1127 in Slot1 of the SCXI, but it should work with a 1128 in Slot8 as well.....

The information, which channel is represented by which sample is quite clear by looking at the graph if you have unique signal values (e.g. DC voltages) on each channel. Then you know haw the signals are covered in the array and you will be able to easily "distribute the appropriate samples to the appropriate channels".

Norbert B.
NI Germany

[bigmatzeman]

Thank you Norbert

do you see any other possibility to get the required informations from the SCXI 1128 and the PXI 4070, because in the Slot 4 of the 1052 combo chassis is a PXI 6281 placed, wich is necessary for the one 1121 and the six 1125 cards in the SCXI chassis. Do you have maybe an example, how this configuration could be work with an aceptable speed?

[Norbert_B]

Bigmatzeman,

finally, i got a working solution which should suite you!
Ok, here is what you have to do/what is missing in your setup:
First, you can leave the modules as they are already inserted in your chassis.
Second, you will need a special AUX-cable to synchronize the DMM and the switch. You can find infos on that here in the section "Single Module Scanning". Connect the cable between the DMM and the front connector of the switch (1331, scanadv. and externaltrig.)
Third, i advise you to use the HV8-BAN4-cable to connected the signals to your DMM. This is because the cable is specified for the appropriate voltage the DMM and the switch are capable of (300 V). The connection of the HV8 can be done in the 1052 above the PXI-slots.
And at last, open the example "niSwitch DMM Switch Handshaking.vi", set the devices to the appropriate identifiers. Select for both triggers for the DMM "External" and for both triggers of the switch "Front Connector". Change the Scanlist to "ch0:5->com0;". If you are using the HV8-BAN4 instead of direct front connector-connection, you have to change the code a bit, too: insert a "niSwitch Connect Channels" VI in front of the "niSwitch Configure Scan Trigger" which connects "ab0" and "com0".

Ok, now the example should work correctly and you should be able to use all other SCXI modules together with your 6281.

Hope this helps,
Norbert

[Edit]: My setup was 4072, 6052E, 1127 and 1011 (instead of 4070, 6281, 1128 and 1052 as you do). But that should work just the same way.

Message Edited by Norbert B on 08-04-2006 10:36 AM