Configuration and Installation Chapter 3
VXI-MXI User Manual 3-18 © National Instruments Corporation
CLK10 Source
The VXIbus specification requires that Slot 0 devices supply a clock signal, CLK10, on a
differential ECL output. The VXI-MXI can generate the CLK10 signal from an onboard
oscillator (10 MHz with a 50% ±5% duty cycle), route an external clock signal from the front
panel SMB connector labeled EXT CLK to the CLK10 signal, or receive the CLK10 signal. Use
the CLK10 Source Select jumper array to select one of these options, as shown in Figure 3-15.
The VXI-MXI is configured at the factory to be a Slot 0 device driving the CLK10 signal from
the onboard oscillator. If you are installing the VXI-MXI in a slot other than Slot 0, change the
jumper array so that the VXI-MXI is configured to receive the CLK10 signal.
If your VXI-MXI includes the INTX daughter card option, the VXI-MXI has the ability to route
the CLK10 signal from the INTX connector. If you intend to do this, remove the jumper
completely and store it in a safe place in case you need to change your system configuration at a
later date.
Warning: Configuring more than one VXIbus device to drive the CLK10 lines can
damage the VXIbus backplane, the CLK10 drivers on the VXIbus devices, or
both.