r5s77631ay266bgv Renesas Electronics Corporation., r5s77631ay266bgv Datasheet - Page 1424

• Manufacturer Part Number: r5s77631ay266bgv
• Description: Renesas 32-bit Risc Microcomputer Superhtm Risc Engine Family Sh-4a Series
• Manufacturer: Renesas Electronics Corporation.

Section 31 Multimedia Card Interface (MMCIF)
31.7
Figure 31.21 shows the operation flow to apply the card detection function.
Rev. 1.00 Oct. 01, 2007 Page 1358 of 1956
REJ09B0256-0100
Peripheral clock 1
and internal divided
clock are in operation
Only card
identification function
is operating
MMCIF initial setting
Communication
with card
Procedure to Apply the Card Detection Function
Figure 31.21 Operation Flow to Apply the Card Identification Function
Card identification waiting state
Peripheral clock 1 and internal
Peripheral clock 1 and internal
Card identified (inserted)
Card identification mode
divided clock operating
divided clock halted
MMCIF initialization
Set card insert wait
Selects frequency
Card identified?
CDI interrupt
Data transfer
Set CHATR
Read CDB
Read CDB
Start
No
Note:
Yes
Card identification clock is always operating
Sets cycle for chattering elimination pulse
Confirms if card has been inserted to
connector
If card is already inserted, go to MMCIF
initialization.
If card is not inserted, go to card
identification wait.
Peripheral clock 1 and internal divided clock
are halted to stop unnecessary FF
operation.
Wait for card to be inserted to connector
Card is inserted to connector.
Peripheral clock 1 and internal divided clock
are operated to end card identification.
MMCIF registers are initialized to enter
operation state
Selects frequency of transfer clock between
MMCIF and card
Issues commands (CMD0 to CMD3) for
identifying card to transfer data
Data transfer between MMCIF and card
CDIE setting
Interrupt generated