The USB-6210 only has two counters; therefore you will not be able to output four different counter pulses from this device. Depending on exactly what you would like to accomplish it may be possible to work around this. For example you can route counter 1 to PFI 5 and to PFI 6 and 7, thus having three counters that output the same pulse train and one that will be different or you can route CTR1 to PFI 5 and PFI7 and then use FREQ out which is PFI6 to divide down to the frequency that you need. Thereby having a combination of 1,2,1 meaning 1 counter on one output, one counter on two outputs and the FREQ OUT on another output.If this is will work for your application then this Developer Zone document will help. If you would like 4 independent counters then I suggest purchasing a separate counter/timer board. I hope this helps!!
JaceD Signal Sources Product Support Engineer National Instruments