ATSAM3U-EK Atmel, ATSAM3U-EK Datasheet - Page 1010

• Manufacturer Part Number: ATSAM3U-EK
• Description: KIT EVAL FOR AT91SAM3U CORTEX
• Manufacturer: Atmel
• Type: MCUr

Specifications of ATSAM3U-EK

• Contents: Board
• Processor To Be Evaluated: SAM3U
• Data Bus Width: 32 bit
• Interface Type: RS-232, USB
• Operating Supply Voltage: 3 V
• Silicon Manufacturer: Atmel
• Core Architecture: ARM
• Core Sub-architecture: Cortex - M3
• Silicon Core Number: SAM3U4E
• Silicon Family Name: SAM3U
• Kit Contents: Board CD Docs
• Rohs Compliant: Yes
• For Use With/related Products: AT91SAM3U
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

39.7.22
Name:
Address:
Access:
Note:
• CHANN_ENB: Channel Enable Status
0 = if cleared, the DMA channel no longer transfers data, and may load the next descriptor if the UDPHS_DMACONTROLx
register LDNXT_DSC bit is set.
When any transfer is ended either due to an elapsed byte count or a UDPHS device initiated transfer end, this bit is auto-
matically reset.
1 = if set, the DMA channel is currently enabled and transfers data upon request.
This bit is normally set or cleared by writing into the UDPHS_DMACONTROLx register CHANN_ENB bit field either by soft-
ware or descriptor loading.
If a channel request is currently serviced when the UDPHS_DMACONTROLx register CHANN_ENB bit is cleared, the
DMA FIFO buffer is drained until it is empty, then this status bit is cleared.
• CHANN_ACT: Channel Active Status
0 = the DMA channel is no longer trying to source the packet data.
When a packet transfer is ended this bit is automatically reset.
1 = the DMA channel is currently trying to source packet data, i.e. selected as the highest-priority requesting channel.
When a packet transfer cannot be completed due to an END_BF_ST, this flag stays set during the next channel descriptor
load (if any) and potentially until UDPHS packet transfer completion, if allowed by the new descriptor.
• END_TR_ST: End of Channel Transfer Status
0 = cleared automatically when read by software.
1 = set by hardware when the last packet transfer is complete, if the UDPHS device has ended the transfer.
Valid until the CHANN_ENB flag is cleared at the end of the next buffer transfer.
• END_BF_ST: End of Channel Buffer Status
0 = cleared automatically when read by software.
1 = set by hardware when the BUFF_COUNT downcount reach zero.
1010
1010
31
23
15
–
7
–
Channel 0 is not used.
SAM3U Series
SAM3U Series
UDPHS DMA Channel Status Register
UDPHS_DMASTATUSx [x = 0..5]
0x400A430C [0], 0x400A431C [1], 0x400A432C [2], 0x400A433C [3], 0x400A434C [4], 0x400A435C [5]
Read-write
DESC_LDST
30
22
14
–
6
END_BF_ST
29
21
13
–
5
END_TR_ST
28
20
12
–
4
BUFF_COUNT
BUFF_COUNT
27
19
11
–
3
–
26
18
10
–
2
–
CHANN_ACT
25
17
9
–
1
6430D–ATARM–25-Mar-11
6430D–ATARM–25-Mar-11
CHANN_ENB
24
16
8
–
0