DMA Controller Module
MCF52110 ColdFire® Integrated Microcontroller Reference Manual, Rev. 1
16-8
Freescale Semiconductor
Preliminary
16.3.5
DMA Control Registers (DCR
n
)
The DMA control registers (DCR
n
) are described in
.
IPSBAR
Offsets:
0x00_010C (DCR0)
0x00_011C (DCR1)
0x00_012C (DCR2)
0x00_013C (DCR3)
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
R
INT
EEXT
CS
AA
BWC
0
0
SINC
SSIZE
DINC
DSIZE
0
W
START
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R
SMOD
DMOD
D_REQ
0
LINKCC
LCH1
LCH2
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 16-8. DMA Control Registers (DCR
n
)
Table 16-4. DCR
n
Field Descriptions
Field
Description
31
INT
Interrupt on completion of transfer. Determines whether an interrupt is generated by completing a transfer or by
the occurrence of an error condition.
0 No interrupt is generated.
1 Internal interrupt signal is enabled.
30
EEXT
Enable external request. Care should be taken because a collision can occur between the START bit and DREQ
n
when EEXT equals 1.
0 External request is ignored.
1 Enables external request to initiate transfer. The internal request (initiated by setting the START bit) is always
enabled.
29
CS
Cycle steal.
0 DMA continuously makes read/write transfers until the BCR decrements to 0.
1 Forces a single read/write transfer per request.
28
AA
Auto-align. AA and SIZE determine whether the source or destination is auto-aligned, that is, transfers are
optimized based on the address and size. See
Section 16.4.4.1, “Auto-Alignment
.”
0 Auto-align disabled
1 If SSIZE indicates a transfer no smaller than DSIZE, source accesses are auto-aligned; otherwise, destination
accesses are auto-aligned. Source alignment takes precedence over destination alignment. If auto-alignment
is enabled, the appropriate address register increments, regardless of DINC or SINC.