Samsung S3C6400X User Manual page 887

S3C6400X RISC MICROPROCESSOR
(4) Check Command Inhibit (DAT) in the Present State register. Repeat this step until Command Inhibit (DAT) is
0.
(5) Set the value corresponding to the issued command in the Argument register.
(6) Set the value corresponding to the issued command in the Command register.
Note: Writing the upper byte in the Command register causes a SD command to be issued.
(7) Perform Command Complete Sequence
COMMAND COMPLETE SEQUENCE
The sequence for completing the SD Command is shown in Figure 27-10. There is a possibility that the errors
(Command Index/End bit/CRC/Timeout Error) occur during this sequence.
(1) Wait for the Command Complete Interrupt. If the Command Complete Interrupt occurs, go to step (2).
(2) Write 1 to Command Complete in the Normal Interrupt Status register to clear this bit.
(3) Read the Response register and get necessary information in accordance with the issued command.
(4) Judge whether the command uses the Transfer Complete Interrupt or not. If it uses Transfer Complete,
proceed with step (5). If not, go to step (7).
(5) Wait for the Transfer Complete Interrupt. If the Transfer Complete Interrupt has occurred, go to step (6).
(6) Write 1 to Transfer Complete in the Normal Interrupt Status register to clear this bit.
(7) Check for errors in Response Data. If there is no error, proceed with step (8). If there is an error, go to step (9).
(8) Return Status of "No Error".
(9) Return Status of "Response Contents Error".
Note1: While waiting for the Transfer Complete interrupt, the Host Driver will only issue commands that do not
use the busy signal.
Note2: The Host Driver judges the Auto CMD12 complete by monitoring Transfer Complete.
Note3: When the last block of un-protected area is read using memory multiple blocks read command (CMD18),
OUT_OF_RANGE error may occur even if the sequence is correct. The Host Driver must ignore it. This error will
appear in the response of Auto CMD12 or in the response of the next memory command.
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
HSMMC CONTROLLER
27-11