![Samsung S3C2451X Скачать руководство пользователя страница 514](http://html.mh-extra.com/html/samsung/s3c2451x/s3c2451x_user-manual_340826514.webp)
Preliminary
HSMMC CONTROLLER
S3C2451X RISC MICROPROCESSOR
21-46
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.
This bit is set at the falling edge of
Write Transfer Active
Status (After getting
CRC status at SD Bus timing).
‘1’ = Transaction stopped at block gap
‘0’ = No
Block Gap Event
STATRANC
MPLT
[1]
Transfer Complete
This bit is set when a read / write transfer is completed.
(1) In the case of a Read Transaction
This bit is set at the falling edge of
Read Transfer Active
Status. There are
two cases in which this interrupt is generated. The first is when a data transfer
is completed as specified by data length (After the last data has been read to
the Host System). The second is when data has stopped at the block gap and
completed the data transfer by setting the
Stop At Block Gap Request
in the
Block Gap Control
register (After valid data has been read to the Host
System).
(2) In the case of a Write Transaction
This bit is set at the falling edge of the
DAT Line Active
Status. There are two
cases in which this interrupt is generated. The first is when the last data is
written to the SD card as specified by data length and the busy signal
released. The second is when data transfers are stopped at the block gap by
setting
Stop At Block Gap Request
in the
Block Gap Control
register and
data transfers completed. (After valid data is written to the SD card and the
busy signal released). (RW1C)
The table below shows that
Transfer Complete
has higher priority than
Data Timeout Error
. If both bits are set to 1, the data transfer can be
considered complete.
Relation between Transfer Complete and Data
Transfer
Complete
Data Timeout
Error
Meaning of the status
0
0
Interrupted by another factor
0
1
Timeout occur during transfer
1
Don’t care
Data transfer complete
‘1’ = Data Transfer Complete
‘0’ = No transfer complete
0
STACMDC
MPLT
[0]
Command Complete
This bit is set when get the end bit of the command response. (Except Auto
CMD12) Refer to
Command Inhibit (CMD)
in the
Present State
register.
The table below shows that
Command Timeout Error
has higher priority
than
Command Complete
. If both bits are set to 1, it can be considered that
the response was not received correctly.
Command
Complete
Command
Timeout Error
Meaning of the status
0
0
Interrupted by another factor
Don’t care
1
Response not received within
64 SDCLK cycles.
1 0
Response
received
‘1’ = Command Complete
‘0’ = No command complete
0
Note :
Host Driver may check if interrupt is actually cleared by polling or monitoring the INTREQ port. If HCLK is
much faster than SDCLK, it takes long time to be cleared for the bits actually.
Note :
Card Interrupt status bit keeps previous value until next card interrupt period (level interrupt) and can be
cleared when write to 1 (RW1C).