K60P100M100SF2RM Datasheet, PDF (1641/1809 Pages) Freescale Semiconductor, Inc – K60 Sub-Family Reference Manual

Chapter 52 Secured digital host controller (SDHC)
CLK
CMD
CMD01
CMD0/Reset
CMD1 RESP CMD2 RESP CMD3 RESP
DAT[0]
S 010 E
S 512bytes E
+CRC
S 512bytes E
+CRC
Min 74
clocks
required
after
power is
stable to
start boot
command
NOTE 1.
50ms
max
1 sec.max
CMD0 with argument 0xFFFFFFFA
Figure 52-38. MultiMediaCard state diagram (alternative boot mode)
52.6 Initialization/application of SDHC
All communication between system and cards are controlled by the host. The host sends
commands of two types: broadcast and addressed (point-to-point).
Broadcast commands are intended for all cards, such as "GO_IDLE_STATE",
"SEND_OP_COND", "ALL_SEND_CID" and etc. In broadcast mode, all cards are in the
open-drain mode to avoid bus contention. Refer to Commands for MMC/SD/SDIO/CE-
ATA for the commands of bc and bcr categories.
After the broadcast command CMD3 is issued, the cards enter standby mode. Addressed
type commands are used from this point. In this mode, the CMD/DAT I/O pads will turn
to push-pull mode, to have the driving capability for maximum frequency operation.
Refer to Commands for MMC/SD/SDIO/CE-ATA for the commands of ac and adtc
categories.
52.6.1 Command send and response receive basic operation
Assuming the data type WORD is an unsigned 32-bit integer, the below flow is a
guideline for sending a command to the card(s):
send_command(cmd_index, cmd_arg, other requirements)
{
WORD wCmd; // 32-bit integer to make up the data to write into Transfer Type register, it is
recommended to implement in a bit-field manner
wCmd = (<cmd_index> & 0x3f) >> 24; // set the first 8 bits as '00'+<cmd_index>
set CMDTYP, DPSEL, CICEN, CCCEN, RSTTYP, DTDSEL accorind to the command index;
if (internal DMA is used) wCmd |= 0x1;
if (multi-block transfer) {
set MSBSEL bit;
if (finite block number) {
K60 Sub-Family Reference Manual, Rev. 6, Nov 2011
Freescale Semiconductor, Inc.
1641