
E X T E R N A L D M A
DMA Control register
348
Hardware Reference NS9215
Register bit
assignment
Bit(s)
Access
Mnemonic
Reset
Description
D31
R/W
CE
0
Channel enable
Enables and disables DMA operations as required.
After a DMA channel has entered the IDLE state
for any reason, this field must be written to a 1 to
initiate further DMA transfers.
D30
R/W
CA
0
Channel abort
When set, causes the current DMA operation to
complete and closes the buffer.
D29
R/W
CG
0
Channel go
When set, causes the DMA channel to exit the
IDLE state and begin a DMA transfer. The CE
field 31) must also be set, which allows software
to initiate a memory-to-memory transfers.
The dma_req and dma_done signals are not used
during memory-to-memory transfers.
D28:27
R/W
SW
0
Source width
Defines the data bus width of the device attached
to the source address specified in the buffer
descriptor.
00
8 bit
01
16 bit
10
32 bit
11
Reserved
D26:25
R/W
DW
0
Destination width
Defines the data bus width of the device attached
to the destination address specified in the buffer
descriptor.
00
8 bit
01
16 bit
10
32 bit
11
Reserved
D24:23
R/W
SB
0
Source burst
Defines the AHB maximum burst size allowed
when reading from the source. Note that the
source must have enough data, as defined by this
register setting, before asserting REQ.
00
1 unit as set by the source width field
(D28:27)
01
4 bytes (Recommended for 8-bit devices)
10
16 bytes (Recommended for 16-bit devices)
11
32 bytes (Recommended for 32-bit devices)
Summary of Contents for NS9215
Page 1: ...NS9215 Hardware Reference 90000847_C Release date 10 April 2008...
Page 3: ......
Page 4: ......
Page 26: ...26 Hardware Reference NS9215...
Page 44: ...P I N O U T 26 5 System clock 44 Hardware Reference NS9215 System clock drawing...
Page 52: ...P I N O U T 26 5 Power and ground 52 Hardware Reference NS9215...
Page 80: ...I O C O N T ROL M O D U L E Memory Bus Configuration register 80 Hardware Reference NS9215...
Page 136: ...WOR KI N G W I TH T H E C P U Noncachable instruction fetches 136 Hardware Reference NS9215...
Page 202: ...S Y S T E M C O N T RO L M OD U L E RTC Module Control register 202 Hardware Reference NS9215...
Page 354: ...E X T E R N A L D M A DMA Peripheral Chip Select register 354 Hardware Reference NS9215...
Page 472: ...R E A L TI M E C L O C K M O D U L E General Status register 472 Hardware Reference NS9215...
Page 512: ...TI M I NG Clock timing 512 Hardware Reference NS9215...
Page 515: ...PA CKA GING Processor Dimensions www digiembedded com 515...
Page 516: ...PA CKA GING Processor Dimensions 516 Hardware Reference NS9215...