Chapter 3
Connecting the Signals
©
National Instruments Corporation
3-11
SCXI-1141/1142/1143 User Manual
The digital input signals are pins 25, 27, 29, and 37. Each digital line
emulates an SCXIbus communication signal as follows:
•
Pin 25 is SERDATIN and is equivalent to the SCXIbus MOSI serial
data input line.
•
Pin 27 is DAQD*/A and is equivalent to the SCXIbus D*/A line.
Pin 27 indicates to the module whether the incoming serial stream on
SERDATIN is data (DAQD*/A = 0) or address (DAQD*/A = 1)
information.
•
Pin 29 is SLOT0SEL* and is equivalent to the SCXIbus INTR* line.
Pin 29 indicates whether the data on the SERDATIN line is being sent
to Slot 0 (SLOT0SEL* = 0) or to a module (SLOT0SEL* = 1).
•
Pin 37 is SERCLK and is equivalent to the SCXIbus SPICLK line.
Pin 37 is used to clock the serial data on the SERDATIN line into the
module registers.
The digital output signal is pin 26. Pin 26 is SERDATOUT and is equivalent
to the SCXIbus MISO serial data output line.
The digital I/O signals of the SCXI-1141/1142/1143 module correspond to
the digital I/O lines of an E Series MIO DAQ device. Table 3-2 lists the
equivalencies.
Table 3-2.
SCXIbus to SCXI-1141/1142/1143 Module Rear Signal Connector
to DAQ Device Pin Equivalencies
SCXIbus Line
SCXI-1141/1142/1143
Rear Signal Connector
E Series MIO
DAQ Device
MOSI
SERDATIN
DIO0
D*/A
DAQD*/A
DIO1
INTR*
SLOT0SEL*
DIO2
SPICLK
SERCLK
EXTSTROBE*
MISO
SERDATOUT
DIO4
An * means the signal is asserted low.
