National Instruments AT-MIO-16X - page 107

Chapter 4 Register Map and Descriptions
© National Instruments Corporation 4-11 AT-MIO-16X User Manual
9 EXTREFDAC1 External Reference for DAC 1—This bit
controls the reference selection for DAC
1 in the analog output section. If this bit
is set, the reference used for DAC 1 is the
external reference voltage from the I/O
connector. If this bit is cleared, the
internal +10 Vref is used for the DAC 1
reference.
8 EXTREFDAC0 External Reference for DAC 0—This bit
controls the reference selection for
DAC 0 in the analog output section. If
this bit is set, the reference used for DAC
0 is the external reference voltage from
the I/O connector. If this bit is cleared,
the internal +10 Vref is used for the DAC
0 reference.
7 EISA_DMA EISA Computer DMA—This bit controls
the type of DMA transfer from the ADC
FIFO on an EISA computer. If
EISA_DMA is clear, single transfer
DMA mode is used. If EISA_DMA is set,
demand-mode DMA is used. This bit
should only be set if the AT-MIO-16X is
installed in an EISA-type computer.
6 0 Reserved—This bit must always be set to
zero.
5-3 DMACHBB<2..0>
DMA Channel B Select—These bits
select the secondary DMA channel for
use by the AT-MIO-16X. See Table 4-2.
2-0 DMACHAB<2..0>
DMA Channel A Select—These bits
select the primary DMA channel for use
by the AT-MIO-16X. See Table 4-2.