National Instruments SCXI-1120 - Manual (Page 84)

Chapter 5 Programming
© National Instruments Corporation 5-13 SCXI-1120 User Manual
3. Follow the steps outlined in the section earlier in this chapter, 3. Programming the Slot 0
Hardscan Circuitry, where step 3, Write the Slot 0 scan list to the FIFO, consists of the
following:
Write 00000000 00000011 to the FIFO Register. This corresponds to Slot 1 for four
samples.
4. Follow the procedure given in the 4. Acquisition Enable, Triggering, and Servicing section
earlier in this chapter.
Example 2
An SCXI-1000 chassis has four SCXI-1120 modules in Slots 1, 2, 3, and 4. The SCXI-1120 in
Slot 4 is cabled to the data acquisition board. You want to scan channels 3 through 7 on the
SCXI-1120 in Slot 1, channels 0 through 6 on the SCXI-1120 in Slot 4, and channels 7 through 3
on the SCXI-1120 in Slot 3.
The programming steps are as follows:
1. Program your data acquisition board as described in the 1. Data Acquisition Board Setup
Programming section.
2. Following the procedure given in the Register Writes section, write 00000000 00000000
to the Configuration Register of the SCXI-1120 in Slot 2. This step resets the module,
including the clearing of the AB0EN bit (bit 0). Notice that a complete reset of this module
is not necessary, but is used for simplicity.
3. Following the procedure given in the Register Writes section, write 10XXX000 00001111
to the Configuration Register of the SCXI-1120 in Slot 4.
4. Following the procedure given in the Register Writes section, write 01XXX011 00001111
to the Configuration Register of the SCXI-1120 in Slot 1.
5. Following the procedure given in the Register Writes section, write 01XXX111 00001111
to the Configuration Register of the SCXI-1120 in Slot 3. Notice that after Channel 7, the
SCXI-1120 will wrap around to Channel 0.
6. Follow the steps given in the section earlier in this chapter, 3. Programming the Slot 0
Hardscan Circuitry, where step 3, Write the Slot 0 scan list to the FIFO, consists of the
following:
a. Write 00000000 00000100 to the FIFO Register. This corresponds to Slot 1 for five
samples.
b. Write 00000001 10000110 to the FIFO Register. This corresponds to Slot 4 for
seven samples.
c. Write 00000001 00000100 to the FIFO Register. This corresponds to Slot 3 for five
samples.
Make sure to toggle SLOT0SEL* or reselect the FIFO Register from scratch between steps
6a, 6b, and 6c.