National Instruments SCXI-1160, User Manual, Page: 46 / 112

Chapter 3 Theory of Operation
© National Instruments Corporation 3-5 SCXI-1160 User Manual
Table 3-1. SCXIbus Equivalents for the Rear Signal Connector
Rear Signal Connector
Signal
SCXIbus Equivalent
SERDATIN MOSI
DAQD*/A D*/A
SLOT0SEL* INTR*
SERCLK SPICLK
SERDATOUT MISO Jumper W5 must be set to position 1
The SCXI-1160 module converts the data acquisition board signals to open-collector signals on
the backplane of the SCXI chassis. For the data acquisition board to talk to a slot, the board must
first assert the SS* for that slot. To do this, assert INTR* low, write a 16-bit number over MOSI
corresponding to the desired slot (and chassis if you are using an SCXI-1001 chassis), and then
release INTR* high. At this point, the SS* of the desired slot is asserted low and the data
acquisition board can communicate with the module in that slot according to the SPI protocol.
Digital Interface
Figure 3-3 shows a diagram of the SCXI-1160 and SCXIbus digital interface circuitry.
Digital
Interface
SCXIbus
Buffered Serial
Data
Buffered Digital
Signal Controls
SERDATIN
DAQD*/A
SLOT0SEL*
SERCLK
SERDATOUT
Rear
Signal Connector
MISO
SPICLK
INTR*
D*/A MOSI
SS*
Figure 3-3. Digital Interface Circuitry Block Diagram