MSC8144E Reference Manual, Rev. 3
14-30
Freescale
Semiconductor
Direct Memory Access (DMA) Controller
Setting an Sx bit defrosts the corresponding channel source. Setting a Dx bit defrosts the
corresponding channel destination. Defrosting a channel allows it to return to normal functioning.
This register is write only; writing a 1 to a bit toggles its value (that is, if the value is 0, it sets the
bit and if it is 1, it clears the bit). Writing a zero to the bits has no effect. The DMACHDFR bits
are all set by reset. Activating a channel sets the corresponding DMACHDFR bits (Sx and Dx).
The register allows simultaneous defrosting of channels
14.6.7 DMA Time-To-Dead Line Registers x (DMAEDFTDLx)
Table 14-18 describes the fields of DMAEDFTDL[0–15].
DMAEDFTDL[0–15]
DMA Time-To-Dead Line Registers 0–15
Offset 0x234 + x*0x4
Bit
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
ENC
—
CURRENT_COUNT
Type
R/W
R
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
THRESHOLD
BASE_COUNT
Type
R/W
Reset
0
0
0
0
0
0
1
0
1
1
1
1
1
1
1
1
Table 14-18. DMAEDFTDL[0–15] Field Descriptions
Bits
Reset
Write By
Description
Settings
ENC
31
0
User
ENC
This field enable this counter. The counter will start
counting when a task is asserted and this field set.
Note:
Enabling and disabling the channels change
the counters value. Disabling channels stops
the counting and enabling them reloads the
counters with their base values.
0 Counter
disabled
1 Counter
enabled
—
30–24
0
Reserved. Write to zero for future compatibility.
CURRENT_
COUNT
23–16
0
DMA
Current Counter Value
This field holds the current value of the counter. Upon
enabling the channel the counter is loaded with the
base value. The counter counts down as long as the
channel is enabled. The counter will stop counting
when the channel is disabled or when counter reached
zero and task is not completed yet. The counter
resumes counting when the buffer ends according to
the BD_ATTR[EDF].
THRESHOLD
15–8
0x02
User
Time to Dead Line Threshold
The threshold defines the value of the counter when
the DMA task is due. The maximum threshold value is
0xff and the minimum is 2.
Note:
The DMA logic sets the priority of the
channels according to counters threshold
value.
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 ...