Product manual

4-28 SanDisk miniSD Card Product Manual, Rev. 1.1 © 2003 SANDISK CORPORATION
4.11.1. Command and Response
Both host command and card responses are clocked out with the rising edge of the host clock.
Card identification and card operation conditions timing
The timing for CMD2 and ACMD41 is given bellow. The command is followed by a period of two Z bits (allowing
time for direction switching on the bus) and then by P bits pushed up by the responding card. The card response to
the host command starts after N
ID
clock cycles.
<------Host command ----> <-N
ID
cycles -> <--- CID or OCR --->
CMD S T content CRC E Z Z P * * * P S T content Z Z Z
Figure 4-12. Identification Timing (Card Identification Mode)
Assign a card relative address
The SEND_RELATIVE_ADDR (CMD 3) for miniSD Card timing is given bellow. Note that CMD3 command’s
content, functionality and timing are different for MultiMediaCard. The minimum delay between the host command
and card response is N
CR
clock cycles.
<---- Host command ----> <-N
CR
cycles-> <-------- Response --------->
CMD S T content CRC E Z Z P * * * P S T content CRC E Z Z Z
Figure 4-13. SEND_RELATIVE_ADDR Timing
Data transfer mode
After the card published it own RCA it will switch to data transfer mode. The command is followed by a period of
two Z bits (allowing time for direction switching on the bus) and then by P bits pushed up by the responding card.
This timing diagram is relevant for all responded host commands except and ACMD41 and CMD2.
<---- Host command ----> <-N
CR
cycles-> <-------- Response --------->
CMD S T content CRC E Z Z P* * *P S T content CRC E Z Z Z
Figure 4-14. Command Response Timing (Data Transfer Mode)
Last Card Response—Next Host Command Timing
After receiving the last card response, the host can start the next command transmission after at least N
RC
clock
cycles. This timing is relevant for any host command.
<-------- Response --------> <-N
RC
cycles-> <---- Host command ----->
CMD S T content CRC E Z * * * * * * Z S T content CRC E
Figure 4-15. Timing Response End to Next CMD Start (Data Transfer Mode)
Last Host Command—Next Host Command Timing
After the last command has been sent, the host can continue sending the next command after at least N
CC
clock
periods.
<----- Host command ----> <-N
CC
cycles-> <---- Host command ----->
CMD S T content CRC E Z * * * * * * Z S T content CRC E
Figure 4-16. Timing of Command Sequences (All Modes)