DMA Registers
671
SLAU356I – March 2015 – Revised June 2019
Copyright © 2015–2019, Texas Instruments Incorporated
DMA
11.3.21 DMA_ALTSET Register (offset = 1030h) [reset = 0h]
DMA Channel Primary-Alternate Set Register. The Channel primary-alternate set register enables you to
configure a DMA channel to use the alternate data structure. Reading the register returns the status of
which data structure is in use for the corresponding DMA channel.
Figure 11-31. DMA_ALTSET Register
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
SET
rw-0
Table 11-35. DMA_ALTSET Register Field Descriptions
Bit
Field
Type
Reset
Description
31-0
SET
RW
0h
Returns the channel control data structure status, or selects the
alternate data structure for the corresponding DMA channel.
Read as: Bit [C] = 0 DMA channel C is using the primary data
structure.
Bit [C] = 1 DMA channel C is using the alternate data structure.
Write as: Bit [C] = 0 No effect.
Use the DMA_ALTCLR Register to set bit [C] to 0.
Bit [C] = 1 Selects the alternate data structure for channel C.
Writing to a bit where a DMA channel is not implemented has no
effect.
Note: The controller toggles the value of the chnl_pri_alt_set [C] bit
after it completes:
the four transfers that the primary data structure specifies for a
memory scatter-gather, or peripheral scatter-gather, DMA cycle
all the transfers that the primary data structure specifies for a ping-
pong DMA cycle
all the transfers that the alternate data structure specifies for the
following DMA cycle types: ping-pong, memory scatter-gather, or
peripheral scatter-gather.