MSC8144E Reference Manual, Rev. 3
14-48
Freescale
Semiconductor
Direct Memory Access (DMA) Controller
NO_INC
43
Increment Address
Indicates the behavior of the buffer address after a request is
serviced. When a dimension is processed, the DMA adds the next
dimension offset to the address, regardless of the status of
NO_INC.
0 Increment
address.
1 Do not increment address.
—
42
Reserved. Write to zero for future compatibility.
NBD
41–32
Next Buffer
When size reaches zero, CONT is set, and the CONTD
dimension count reaches zero, the next request calls the buffer to
which NBD points.
Note:
For four dimensional buffers, if CONT is set, NBD must
be different from the current BD.
CNT
31–30
Channel Counter
This field is valid only for a destination buffer only when the
arbitration is time-based. It characterizes the time-based
arbitration mechanism for continuous buffers when the buffer size
reaches zero and applies only when switching buffers.
00
Continuous: Channel and counter
continue working normally.
01 Reserved.
10 Reserved.
11
Resets the channel counter.
PP
29–28
Port Priority
Defines the priority for the designated buffer. The bus interface
sets the priority for this buffer. You must map the priority at the
system level.
00 Priority 0 (lowest.).
11 Priority 3 (highest).
TSZ
27–24
Transfer Size
Indicates the maximum transfer size that the DMA controller
issues when a request is detected.
0000
512 bytes.
0001 1
byte.
0010 2
bytes.
0011 4
bytes.
0100 8
bytes.
0101
16 bytes.
0110 32
bytes.
0111 64
bytes.
1000 128
bytes.
1001 256
bytes.
1010 512
bytes.
1011 1024
bytes.
11xx Reserved.
—
23
Reserved. Write to zero for future compatibility.
FRZ
22
Freeze Channel
When size reached zero the channel can be freeze. The already
serviced requests continue normally. No further requests are
issued for the associated channel until the host defrost it. See
also the FRZD field.
0 Normal
operation.
1 Freeze channel when size reaches
zero on the dimension selected by
FRZD.
MR
21
Mask Requests Until Data Reached Destination
Indicates the behavior of the logic when BD_MD_SIZE reaches
zero. In continuous buffers, the channel is usually not masked.
There is an automatic mask when ports are switched in a
continuous buffer. The DMA controller unmasks the requests
when last data reaches the destination. See also the MRD field.
0 Normal
operation.
1 Mask requests until data reached
destination on the dimension selected
by MRD.
Table 14-31. BD_MD_ATTR Field Descriptions (Continued)
Bits
Description
Settings
Summary of Contents for MSC8144E
Page 1: ...MSC8144E Reference Manual Quad Core Media Signal Processor MSC8144ERM Rev 3 July 2009 ...
Page 48: ...MSC8144E Reference Manual Rev 3 xlviii Freescale Semiconductor ...
Page 86: ...MSC8144E Reference Manual Rev 3 1 38 Freescale Semiconductor Overview ...
Page 168: ...MSC8144E Reference Manual Rev 3 3 60 Freescale Semiconductor External Signals ...
Page 242: ...MSC8144E Reference Manual Rev 3 5 26 Freescale Semiconductor Reset ...
Page 314: ...MSC8144E Reference Manual Rev 3 8 24 Freescale Semiconductor General Configuration Registers ...
Page 414: ...MSC8144E Reference Manual Rev 3 10 14 Freescale Semiconductor MSC8144E SC3400 DSP Subsystem ...
Page 452: ...MSC8144E Reference Manual Rev 3 11 38 Freescale Semiconductor Internal Memory Subsystem ...
Page 520: ...MSC8144E Reference Manual Rev 3 12 68 Freescale Semiconductor DDR SDRAM Memory Controller ...
Page 1070: ...MSC8144E Reference Manual Rev 3 21 28 Freescale Semiconductor Timers ...