HSMMC CONTROLLER
S3C2416X RISC MICROPROCESSOR
20-4
4.2 SD CLOCK SUPPLY SEQUENCE
START
Calculate a divisor for SD Clock frequency
Set SDCLK frequency select and
Internal Clock Enable
Check Internal Clock
Enable
Set SD Clock ON
End
(1)
(2)
(3)
(4)
Figure 20-3. SD Clock Supply Sequence
The sequence for supplying SD Clock to a SD card is described in Figure 20-3. The clock shall be supplied to the
card before either of the following actions is taken.
a) Issuing a SD command
b) Detect an interrupt from a SD card in 4-bit mode.
(1) Calculate a divisor to determine SD Clock frequency by reading Base Clock Frequency for SD Clock in the
Capabilities register. If Base Clock Frequency for SD Clock is 00 0000b, the Host System shall provide this
information to the Host Driver by another method.
(2) Set Internal Clock Enable(ENINTCLK) and SDCLK Frequency Select in the Clock Control register in
accordance with the calculated result of step (1).
(3) Check Internal Clock Stable(STBLINTCLK) in the Clock Control register. Repeat this step until Clock Stable is
1.
(4) Set SD Clock Enable(ENSDCLK) in the Clock Control register to 1. Then, the Host Controller starts to supply
the SD Clock.
Summary of Contents for S3C2416
Page 122: ...BUS MATRIX EBI S3C2416X RISC MICROPROCESSOR 3 4 NOTES ...
Page 204: ...DMA CONTROLLER S3C2416X RISC MICROPROCESSOR 8 18 NOTES ...
Page 284: ...WATCHDOG TIMER S3C2416X RISC MICROPROCESSOR 11 6 NOTES ...
Page 320: ...REAL TIME CLOCK S3C2416X RISC MICROPROCESSOR 13 16 NOTES ...
Page 344: ...UART S3C2416X RISC MICROPROCESSOR 14 24 NOTES ...
Page 380: ...USB2 0 DEVICE S3C2416X RISC MICROPROCESSOR 16 34 NOTES ...
Page 432: ...2D S3C2416X RISC MICROPROCESSOR 18 38 NOTES ...
Page 446: ...HS_SPI CONTROLLER S3C2416X RISC MICROPROCESSOR 19 14 NOTES ...
Page 604: ...S3C2416X RISC MICROPROCESSOR S3C2416X RISC MICROPROCESSOR 23 22 NOTES ...
Page 638: ...PCM AUDIO INTERFACE S3C2416X RISC MICROPROCESSOR 25 18 NOTES ...
Page 670: ...ELECTRICAL DATA S3C2416X RISC MICROPROCESSOR 26 32 NOTES ...