RS_SDIO controller
RM0082
686/844
Doc ID 018672 Rev 1
Figure 72.
Command issue sequence
1.
Check Command Inhibit (CMD) in the Present State register. Repeat this step until
Command Inhibit (CMD) is logic ‘0’.
2.
If the Host Driver issues a SD Command with busy signal, go to step (3). If without busy
signal, go to step (5).
3. If the Host Driver issues an abort command, go to step (5). In the case of no abort
command, go to step (4).
4. Check Command Inhibit (DAT) in the Present State register. Repeat this step until
Command Inhibit (DAT) is set to logic ‘0’.
5.
Set the value of command argument to the Argument register.
6.
Set the Command register.
7.
Perform Command Completion Sequence.
Start
End
(1)
(5)
Check Command
Inhibit (CMD)
CMD Line free
Issue the command
with the busy?
Yes
Issue Abort
Command?
No
Check Command
Inhibit(DAT)
DAT Lone used
DAT Lone free
New command can be issued
Set Argument Reg
Set Command Reg
Command Complete Sequence
CMD Line used
(2)
(3)
(4)
(6)
(7)
Yes
No