Configuration and Installation Chapter 3
VXI-MXI User Manual 3-20 © National Instruments Corporation
EXT CLK SMB Input/Output
If you want to have synchronized CLK10 signals in multiple VXIbus mainframes, you can
connect the CLK10 signals of the two mainframes together using the EXT CLK SMB connectors
on the front panel of the VXI-MXI. One mainframe should source the CLK10 signal to the SMB
connection. The other device receives the CLK10 signal from the SMB connection and drives it
on the VXIbus CLK10 lines. This device must be installed in Slot 0 so that it can drive the
VXIbus CLK10 signal. For this option, set the CLK10 Source Select jumpers to select an
external clock as shown in Figure 3-15(b).
Slide switch S6 sets whether the EXT CLK SMB is used as an input to receive a CLK10 signal
to drive on the VXIbus, or as an output to source the CLK10 signal to another VXIbus
mainframe. Figure 3-16 shows the two settings of slide switch S6.
S6
a. Drive EXT CLK
(Default Setting)
CLK10 out SMBCLK10 in from SMB
S6
b. Receive EXT CLK
CLK10 out SMBCLK10 in from SMB
Figure 3-16. EXT CLK SMB Input/Output Setting
INTX CLK10 Mapping
If your VXI-MXI includes the INTX daughter card option, you can use the INTX CLK10 Routing
switches to route the CLK10 signal to or from the INTX connector. The INTX daughter card is
shipped from the factory with the CLK10 mapping function disabled. Refer to Figure 3-2 to
view the location of the three slide switches used to configure the INTX CLK10 mapping.
Figure 3-17 shows how to set these switches to (a) disable CLK10 mapping, (b) enable CLK10
to map out of the mainframe through the INTX connector, or (c) enable CLK10 into the
mainframe from the INTX connector.