Atmel SAM9X25, Manual

Page: 616 / 1145

616
11054A–ATARM–27-Jul-11
SAM9X25
Figure 34-9. Write Functional Flow Diagram
Note: 1. It is assumed that this command has been correctly sent (see Figure 34-7 ).
2. This field is also accessible in the HSMCI Block Register (HSMCI_BLKR).
Send SELECT/DESELECT_CARD
command
(1)
to select the card
Send SET_BLOCKLEN command
(1)
Write using DMAC
Send WRITE_SINGLE_BLOCK
command
(1)
Configure the DMA channel X
DMAC_DADDRx = Data Address to write
DMAC_BTSIZE = BlockLength/4
Send WRITE_SINGLE_BLOCK
command
(1)
Read status register HSMCI_SR
Poll the bit
XFRDONE = 0?
Yes
No
Yes
No
Read status register HSMCI_SR
Number of words to write = 0 ?
Poll the bit
TXRDY = 0?
HSMCI_TDR = Data to write
Number of words to write =
Number of words to write -1
Yes
RETURN
No
Yes
No
Number of words to write = BlockLength/4
DMAC_CHEN[X] = TRUE
Reset theDMAEN bit
HSMCI_DMA &= ~DMAEN
Set the block length (in bytes)
HSMCI_MR |= (BlockLength) <<16)
(2)
Set the block count (if necessary)
HSMCI_BLKR |= (BlockCount << 0)
Set the DMAEN bit
HSMCI_DMA |= DMAEN
Set the block length (in bytes)
HSMCI_BLKR |= (BlockLength << 16)
(2)
RETURN