MSC8144E Reference Manual, Rev. 3
17-22
Freescale
Semiconductor
RapidIO Interface Dedicated DMA Controller
CDSM/SWSM
4
0
Current Descriptor Start Mode/Single-Write Start
Mode
The function of this bit varies depending on the
setting of XFE, CTM, and SRW.
Note:
This bit must be cleared when SRW is
cleared.
CTM = 0 and XFE = 0
0
Normal operation.
1
Single-write start mode in which a
write to the current link descriptor
address register sets MR[CS] to
start the DMA transfer.
CTM = 0 and XFE = 1
0
Normal operation.
1
Single-write start mode in which a
write to the current list descriptor
address register sets MR[CS] to
start the DMA transfer.
CTM = 1 and SRW = 0
0
Normal operation.
1
A write to the current link
descriptor address register sets
MR[CS] to initiate a DMA transfer.
CTM = 1 and SRW = 1
0
A write to the destination address
register sets MR[CS] to initiate a
DMA transfer.
1
A write to the source address
register sets MR[CS] to initiate a
DMA transfer.
CA
3
0
Channel Abort
When set, causes the channel to abort the transfer
and clear CB. The channel then remains idle until a
new transfer is programmed.
0
No effect.
1
Abort current transfer.
CTM
2
0
Channel Transfer Mode
When set, configures the controller in direct mode,
which means that software must place all the
required parameters into the necessary registers to
start the DMA transfer.
0
Chaining mode.
1
Direct mode.
CC
1
0
Channel Continue (chaining mode only)
When set, restarts the transferring process starting
at the current descriptor address. This bit is
reserved in external master mode. The bit is cleared
automatically by hardware after the first descriptor
read when continuing a transfer.
0
No effect.
1
Restarts the DMA transfer at the
current descriptor address.
CS
0
0
Channel Start
Halts or starts the DMA transfer. This bit is set
automatically by hardware during single-write start
mode and external master start enable mode.
0
Stops the DMA transfer if the
channel is busy (SR[CB] is set),
no effect if the channel is idle.
1
Starts the DMA process if the
channel is idle (SR[CB] is
cleared). Setting the bit while the
channel is busy continues the
current transfer from the point at
which it stopped.
Table 17-7. MR Field Descriptions (Continued)
Bits
Reset
Description
Setting
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 ...