Hi again !
Good turorials are avilable at NI homepage I have posted them below..
If you use the DAQmx Assistent you have to use one block for each type
of
signal that you need. Lets say that you want to use two
analog outputs in the same VI, what you do is that you use one DAQmx
Assitent block and add the first of your wanted analog channels. If you
then want to add a second one you only edit the properties of your
block in the block diagram and add a new task for the second channel
(see attched picture). You will then get the two measured voltages from
the same Assistent block, use the "Convert from Dynamic data " block to
extract the two measured signals. However if you want to add a new
digital output or any other signal, except for the analog output, you
will have to add a second DAQmx Assistent block anf then choose the
wanted signal type.
I have to warn you about a trouble I had with my Digital outputs when I
used my USB device. I tried to drive a relay that needed 2.5 mA to
drive. The problem is that the DO of the USB device can only drive
currents up to approx. 0.67 mA. This can be solved by connecting
a external resistance from the +5 V pin to the wanted DO. You will then
be able to drive a maximumk of 8.5 mA. How you should choose your
resistance is described in the manual that you recieved with your USB
device or at the link below.
A simple and basic guide to Labview with good exampels:
http://digital.ni.com/manuals.nsf/websearch/BF4B45DC473C89AE86256D2C0062711E?OpenDocument&node=132090_US
A complete guide to Labview:
http://digital.ni.com/manuals.nsf/websearch/790127B60590AD0C86256D2C005DCE0F?OpenDocument&node=132090_US
This is a site at NI with good manuals for the DAQmx with USB devices (and a manual for the USB 6008 device):
http://digital.ni.com/manuals.nsf/display?ReadForm&lookup=Data%20Acquisition%3E%3EMultifunction%20DAQ%3E%3ESoftware&view=weblastmonth&node=132080_US
Hope that this will help you, if I'm not answering your question tell me !