Renesas SH7781 - Manual (Page 1251)

24. Multimedia Card Interface (MMCIF)
Rev.1.00 Jan. 10, 2008 Page 1221 of 1658
REJ09B0261-0100
Start of command sequence
Clear FIFO
Execute CMD16
Read response register
Execute CMD17
(Set CMDR then CMDSTRT)
Set the size of block
for transfer in TBCR
No
Yes
CRCERI interrupt
detected?
Yes
No CMD16
normal end?
Yes
No
CRPI inte rrupt
detected?
Yes
No
Response status
normal?
Yes
No
End of command sequence
CTERI interrupt
detected?
Yes
No
FFI interrupt
detected?
Set CMDOFF to 1
Read data from FIFO
Set RD_CONTI to 1
Read data from FIFO
No
Yes
DTERI interrupt
detected?
No
Yes
CRCERI interrupt
detected?
No
Yes
Legend:
Len: Block length [bytes]
Cap: FIFO size [bytes]
n (FFI): Number of FIFO full interrupts (FFI) from the start of read sequence
DTERI interrupt
detected?
Yes
No
DTI interrupt
detected?
Yes
No
Cap ≥
Len - Cap × n (FFI)
Set CMDOFF to 1
Clear FIFO
Figure 24.12 Example of Operational Flow for Commands with Read Data
(Single Block Transfer)