RM0082
RS_SDIO controller
Doc ID 018672 Rev 1
685/844
Figure 71.
SD clock supply sequence
1.
Calculate a divisor to determine SD Clock frequency.
2.
Set Internal Clock Enable and SDCLK Frequency Select in the Clock Control register.
3.
Check Internal Clock Stable in the Clock Control register. Repeat this step until Clock
Stable is logic ‘1’.
4.
Set SD Clock Enable in the Clock Control register to logic ‘1’. Then, the Host Controller
starts to supply the SD Clock.
Calculate a divisor for SD
clock frequency
Start
Set SDCLK Frequency Select
and Internal Clock Enable
Check
Internal Clock Stable
End
(1)
(2)
(3)
(4)
Set SD Clock On
Supply SD Clock
Internal Clock Stable = 1b
Internal Clock Stable = 0b