Atmel SAM9X25, Руководство пользователя

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659
11054A–ATARM–27-Jul-11
SAM9X25
34.14.17 HSMCI Configuration Register
Name: HSMCI_CFG
Address: 0xF0008054 (0), 0xF000C054 (1)
Access: Read-write
This register can only be written if the WPEN bit is cleared in “HSMCI Write Protect Mode Register” on page 660 .
• FIFOMODE: HSMCI Internal FIFO control mode
0 = A write transfer starts when a sufficient amount of data is written into the FIFO.
When the block length is greater than or equal to 3/4 of the HSMCI internal FIFO size, then the write transfer starts as soon
as half the FIFO is filled. When the block length is greater than or equal to half the internal FIFO size, then the write transfer
starts as soon as one quarter of the FIFO is filled. In other cases, the transfer starts as soon as the total amount of data is
written in the internal FIFO.
1 = A write transfer starts as soon as one data is written into the FIFO.
• FERRCTRL: Flow Error flag reset control mode
0= When an underflow/overflow condition flag is set, a new Write/Read command is needed to reset the flag.
1= When an underflow/overflow condition flag is set, a read status resets the flag.
• HSMODE: High Speed Mode
0= Default bus timing mode.
1= If set to one, the host controller outputs command line and data lines on the rising edge of the card clock. The Host
driver shall check the high speed support in the card registers.
• LSYNC: Synchronize on the last block
0= The pending command is sent at the end of the current data block.
1= The pending command is sent at the end of the block transfer when the transfer length is not infinite. (block count shall
be different from zero)
31 30 29 28 27 26 25 24
– – – – – –
23 22 21 20 19 18 17 16
– – – – – – – –
15 14 13 12 11 10 9 8
– – – LSYNC – – – HSMODE
7 6 5 4 3 2 1 0
– – – FERRCTRL – – – FIFOMODE