Connecting RTSI line to non-NI PCI card

[GLewen]

I would like to trigger analog output on a PCI-6733 and trigger an non-NI PCI card using the GPCTR0 output. It appears I can direct the GPCTR0 output to the UPDATE for AO on the PCI-6733 and do this internally (say using RTSI-1). If I do this I presume that RTSI-1 will also be mirrored on the "external" RTSI bus and avaliable for triggering?

The non-NI card in question as 5V-tolerant LVTTL inputs. Of what points should I be aware as I proceed? As you can tell from my question I am a bit fuzzy on using the RTSI bus.


Thank You Very Much.

[Matthew C]

Hello GLewen,

Thank you for contacting National Instruments.

If I understand your question correctly, I believe you have the right idea. One of the main purposes of the RTSI bus is to facilitate the synchronization of multiple devices. It is also used to internally route signals. Before using the RTSI bus with DAQmx, you will need to register a RTSI cable in MAX (regardless of whether you are actually using a cable).

If you programmatically route the output of GPCTR0 (i.e. pulse train generation) to your AO Update via RTSI 1, you will literally be placing the pulse train generated by the counter on RTSI 1. You can then use RTSI 1 as the trigger source on other devices.

If you are using a non-NI PCI card, it is unlikely that the card is going to hav
e a RTSI connector on it. In this case, you will need to come up with your own method of harnessing the signal.

There are a few points to be aware of are. Although unlikely, any damage caused to your NI card by doing this could void your warranty. Be careful that you do not drive a RTSI line with multiple sources. This could damage your card.

I hope this helps! If you have further questions about the RTSI bus or internal routing, let me know.

Matthew C
Applications Engineer
National Instruments