Atmel Evaluation Kit AT91SAM9M10-G45-EK AT91SAM9M10-G45-EK Data Sheet
Product codes
AT91SAM9M10-G45-EK
942
SAM9M10 [DATASHEET]
6355F–ATARM–12-Mar-13
8.
If source picture-picture mode is enabled (DMAC_CTRLBx.SRC_PIP is enabled), program the
DMAC_SPIPx register for channel x.
DMAC_SPIPx register for channel x.
9.
If destination picture-in-picture is enabled (DMAC_CTRLBx.DST_PIP is enabled), program the
DMAC_DPIPx register for channel x.
DMAC_DPIPx register for channel x.
10. Clear any pending interrupts on the channel from the previous DMAC transfer by reading the status regis-
ter: DMAC_EBCISR.
12. Program the DMAC_DSCRx register with DMAC_DSCRx(0), the pointer to the first Linked List item.
13. Finally, enable the channel by writing a ‘1’ to the DMAC_CHER.ENABLE[n] bit, where n is the channel
number. The transfer is performed.
14. The DMAC fetches the first LLI from the location pointed to by DMAC_DSCRx(0).
Note:
The LLI.DMAC_SADDRx, LLI. DMAC_DADDRx, LLI.DMAC_DSCRx, LLI.DMAC_CTRLAx and LLI.DMAC_CTRLBx
registers are fetched. The DMAC automatically reprograms the DMAC_SADDRx, DMAC_DADDRx, DMAC_DSCRx,
DMAC_CTRLBx and DMAC_CTRLAx channel registers from the DMAC_DSCRx(0).
registers are fetched. The DMAC automatically reprograms the DMAC_SADDRx, DMAC_DADDRx, DMAC_DSCRx,
DMAC_CTRLBx and DMAC_CTRLAx channel registers from the DMAC_DSCRx(0).
15. Source and destination request single and chunk DMAC transactions to transfer the buffer of data
(assuming non-memory peripheral). The DMAC acknowledges at the completion of every transaction
(chunk and single) in the buffer and carry out the buffer transfer.
(chunk and single) in the buffer and carry out the buffer transfer.
16. Once the buffer of data is transferred, the DMAC_CTRLAx register is written out to system memory at the
same location and on the same layer (DMAC_DSCRx.DSCR_IF) where it was originally fetched, that is,
the location of the DMAC_CTRLAx register of the linked list item fetched prior to the start of the buffer
transfer. Only DMAC_CTRLAx register is written out because only the DMAC_CTRLAx.BTSIZE and
DMAC_CTRLAX.DONE bits have been updated by DMAC hardware. Additionally, the
DMAC_CTRLAx.DONE bit is asserted when the buffer transfer has completed.
the location of the DMAC_CTRLAx register of the linked list item fetched prior to the start of the buffer
transfer. Only DMAC_CTRLAx register is written out because only the DMAC_CTRLAx.BTSIZE and
DMAC_CTRLAX.DONE bits have been updated by DMAC hardware. Additionally, the
DMAC_CTRLAx.DONE bit is asserted when the buffer transfer has completed.
Note:
Do not poll the DMAC_CTRLAx.DONE bit in the DMAC memory map. Instead, poll the LLI.DMAC_CTRLAx.DONE bit
in the LLI for that buffer. If the poll LLI.DMAC_CTRLAx.DONE bit is asserted, then this buffer transfer has completed.
This LLI.DMAC_CTRLAx.DONE bit was cleared at the start of the transfer.
in the LLI for that buffer. If the poll LLI.DMAC_CTRLAx.DONE bit is asserted, then this buffer transfer has completed.
This LLI.DMAC_CTRLAx.DONE bit was cleared at the start of the transfer.
17. The DMAC does not wait for the buffer interrupt to be cleared, but continues fetching the next LLI from the
memory location pointed to by current DMAC_DSCRx register and automatically reprograms the
DMAC_SADDRx, DMAC_DADDRx, DMAC_DSCRx, DMAC_CTRLAx and DMAC_CTRLBx channel reg-
isters. The DMAC transfer continues until the DMAC determines that the DMAC_CTRLBx and
DMAC_DSCRx registers at the end of a buffer transfer match described in Row 1 of
DMAC_SADDRx, DMAC_DADDRx, DMAC_DSCRx, DMAC_CTRLAx and DMAC_CTRLBx channel reg-
isters. The DMAC transfer continues until the DMAC determines that the DMAC_CTRLBx and
DMAC_DSCRx registers at the end of a buffer transfer match described in Row 1 of
. The DMAC then knows that the previous buffer transferred was the last buffer in the DMAC transfer.
.