Preliminary
HSMMC CONTROLLER
S3C2451X RISC MICROPROCESSOR
21-30
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
Status
register and changing from 1 to 0 generates a
Card Removal
interrupt in the
Normal Interrupt Status
register. The
Software Reset For All
in the
Software Reset
register shall not affect this bit. If a card is removed while its power is on and its
clock is oscillating, the Host Controller shall clear
SD Bus Power
in the
Power
Control
register and
SD Clock Enable
in the
Clock Control
register.
When this bit is changed from 1 to 0, the Host Controller shall immediately stop
driving
CMD
and
DAT[3:0]
(tri-state). In addition, the Host Driver should clear the
Host Controller by the
Software Reset For All
in
Software Reset
register. The card
detect is active regardless of the
SD Bus Power
.
1 = Card Inserted
0 = Reset or Debouncing or No Card
[15:14]
Reserved
DIFF4
W
[13]
FIFO Pointer Difference 4-Word (ROC)
When the difference of the address pointer between AHB side and SD side is more
than or equal to 4-word, this status bit is set to HIGH. When others clears
automatically.
Write(Tx) mode : when this bit is HIGH, more than or equal to 4-word can be written
by CPU side.
Read(Rx) mode : when this bit is HIGH, more than or equal to 4-word can be read by
CPU side.
0
DIFF1
W
[12]
FIFO Pointer Difference 1-Word (ROC)
When the difference of the address pointer between AHB side and SD side is more
than or equal to 1-word, this status bit is set to HIGH. When others clears
automatically.
Write(Tx) mode : when this bit is HIGH, more than or equal to 1-word can be written
by CPU side.
Read(Rx) mode : when this bit is HIGH, more than or equal to 1-word can be read by
CPU side.
0
BUFR
DRDY
[11]
Buffer Read Enable
(ROC)
This status is used for non-DMA read transfers. The Host Controller may implement
multiple buffers to transfer data efficiently. This read only flag indicates that valid
data exists in the host side buffer status. If this bit is 1, readable data exists in the
buffer. A change of this bit from 1 to 0 occurs when all the block data is read from
the buffer. A change of this bit from 0 to 1 occurs when block data is ready in the
buffer and generates the
Buffer Read Ready
interrupt.
1 = Read enable
0 = Read disable
0
BUFW
TRDY
[10]
Buffer Write Enable
(ROC)
This status is used for non-DMA write transfers. The Host Controller can implement
multiple buffers to transfer data efficiently. This read only flag indicates if space is
available for write data. If this bit is 1, data can be written to the buffer. A change of
this bit from 1 to 0 occurs when all the block data is written to the buffer. A change of
this bit from 0 to 1 occurs when top of block data can be written to the buffer and
generates the
Buffer Write Ready
interrupt.
1 = Write enable
0 = Write disable
0