National Instruments 800 Series - Manual (Page 32)

Chapter 3 VXIpc 800 Series Configuration and Installation
VXIpc 800 Series User Manual 3-8 © National Instruments Corporation
Trigger Input Termination
You can use switch S7 to terminate the external trigger input SMB
with 50
Ω
to ground. Figure 3-7a shows the default setting for a
non-terminated trigger input SMB. Use the setting of Figure 3-7b to
terminate the trigger input SMB. Switch S7 is located above switches
S4, S5, and S6, which have no effect on this configuration.
Figure 3-7. SMB Trigger Input Termination
EEPROM
The VXIpc-800 has an onboard EEPROM, which stores default register
values for the VXI circuitry. These values are loaded when you power
up the computer. These values read from the EEPROM tell the PCI
interface of the VXIbus registers so that the VXI interface is ready to
respond to Resource Manager accesses within the required 5 s of
SYSRST* deasserting. You can use switch S2 to disable this power-on
self-configuration (POSC) circuit. Although this makes the VXI
circuitry unusable, it is sometimes helpful in debugging address and
interrupt conflicts with add-in boards. In general, however, you should
leave switch S2 in its factory-default setting. Figure 3-8 shows the
possible configurations for S2.
Figure 3-8. Power-On Self Configuration Status
S7 S7
a. Does Not Terminate
Trigger Input (Default)
b. Terminate Trigger Input
S2 S2
a. VXI Circuitry Loads Power-on
Defaults from EEPROM (Default)
b. Power-on Self Configuration
Circuit is Disabled