06-12-2007 09:14 AM
We are newbies using a 6602 with the SCB-68 interface.
We are reading 8 different TTL pulse trains. We've determined that we need buffered periodic event counting (BPEC) and that we need a common clock (source).
We've used the measurement and automation software to confirm that we can see our signal coming into the card. However, we cannot seem to perform functions requiring a clock (e.g. BPEC).
Question: How do we associate an 80 MHz clock to the source for our counter channels? The the card has clocks, yet our error messages indicate that an external clock had to be used for our task. We may be stuck in the meaning of "external". Though a clock is in the card, is it considered external to my counter channel? Do I connect it via jumpers in the SCB-68 or are there ways to associate it via commands?
06-13-2007 03:02 PM
Hi NHJared,
There a few examples in the LabVIEW Example finder that will help you make these measurements. (Help >> Find Examples >> Hardware Input and Output >> DAQmx >> Counter Measurements >> Period or Pulse Width)
The DAQmx Timing VI should be set to implicit. This setting will automatically route the appropriate clock necessary for your measurements. An external clock is a signal that is created by another device other than the PCI-6602 and connected through an external pin on the PCI-6602 (e.g. PFI pin)