I am using the PCI-6534 in pattern output mode sending 32bits of data.I am timing the signals externally. At certain frequencies of the REQ signal the DAQ card stops outputting.The signal sometimes becomes unstable before it cuts out and sometimes the signal changes to a signal of lower frequency. I have tried using different timing devices and the frequency at which it cuts out is different on each.
1)Why would it cut out?
2)Why would the frequency at which it cuts out change due to what signal I am sending in?
Hi Ryan, Can you give an example of a frquency at which the device starts to fail? What type of devices are you using for the frequency source? Also, what kind of cabling do you have between the frequency source and the 6534?
The frequency at which the device starts to fail depends on the what timing device I am using.I have tried 3 devices:
1)A PLL circuit where the signal is coming directly from a VCO chip.I am using a SH68-68-D1 cable to connect to this circuit via a pcb mount scsi connector.This setup fails between 10 and 12MHz aswell as anything above 18Mhz(up to 20MHz limit).
2)A pulse generator using the SCB-68 connector block and the same cable as above. This cuts out at 14MHz and above.
3)A data generator using the same setup as 2).This cuts out 18MHz and above.
