5.7.2.6
HOSTCONTROL - Host-I/F DMA control register
This register controls the function of the DMA request control.
Access
This register can be read/written in 8-bit, 16-bit and 32-bit units.
If this register is read in 16-bit or 32-bit units the upper bits 15 to 8, respectively
31 to 8, return undefined values. Writing to these bits is ignored.
Address
0000001C
H
Initial Value
0000 0000
H
. This register is initialized by any reset.
7
6
5
4
3
2
1
0
0
0
0
0
0
0
DRQDIR
DRQEN
R
R
R
R
R
R
R/W
R/W
Writing to the read-only bits is ignored, reading returns undefined values.
Bit
Bit name
Function
1
DRQDIR
Selects the transfer direction for which the DMA request control is active
0 transmit direction (data transfer to Host CPU)
1 receive direction (data transfer from Host CPU)
0
DRQEN
Enables the operation of the DMA request control unit
0 disable – DMA request control inactive
1 enable – DMA request control active
Host CPU Interface
Chapter 5
Preliminary User's Manual S19203EE1V3UM00
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