13-14
MCF5249UM
MOTOROLA
FlashMedia Interface
13.4.2.3
FLASHMEDIA COMMAND REGISTER 2 in Secure Digital Mode
The commands and their meanings are described in detail later in this section.
21
SENDCRC
0: No CRC inserted
1: packet bits 0-15 will be replaced with
CRC
0
22
WIDESHIFT
0: 1-bit data bus
1: 4-bit data bus
0
Note:
The following codes are relevant for FlashMedia command register 1:
FLASHMEDIACMD1[22:16] = 0x44: wait for read, 4 bit wide
FLASHMEDIACMD1[22:16] = 0x04: wait for read, 1 bit wide
FLASHMEDIACMD1[22:16] = 0x66: write data, 4 bit wide
FLASHMEDIACMD1[22:16] = 0x26: write data, 1 bit wide
FLASHMEDIACMD1[22:16] = 0x00: receive handshake
FLASHMEDIACMD1[22:16] = 0x08: wait for busy signalling
Table 13-12 FLASHMEDIA COMMAND REGISTER 2 (Secure Digital Mode)
FLASHMEDIACMD2
BITS
FIELD
NAME
RW
MEANING
RES
NOTES
15:0
BITCOUNT
ER
RW
Write to this field the number of bits to be
exchanged with the flash card.
Read value is the number of bits
remaining.
0
19:16
CMDCODE
0
20
NEXT BS
next value to output on BS pin
(MemoryStick)
0
21
SENDCRC
reserved, should be 0
0
22
DRIVECMD
0: do not drive command line
1: start driving command line after
receiving card status response
0
23
DRIVEDAT
A
0: do not drive data line
1: start driving data line after command
transmission end.
Note:
The following codes are relevant for FlashMedia command register 2:
FLASHMEDIACMD2[23:16] = 0x46: Send read data command to SD. (drive cmd line after receiving flash
status, do not drive data lines)
FLASHMEDIACMD2[23:16] = 0x40: Receive status for read data command from SD
FLASHMEDIACMD2[23:16] = 0xC6: Send write data command to SD. (Drive cmd line after receiving flash
status. Drive data line after sending command.)
FLASHMEDIACMD2[23:16] = 0xC0: Receive status for write data command from SD
FLASHMEDIACMD2[23:16] = 0x06: Send non-data command to SD
FLASHMEDIACMD2[23:16] = 0x00: Receive status for non-data command, stop driving cmd and data lines.
Table 13-11 FLASHMEDIA COMMAND REGISTER 1 (Secure Digital Mode) (Continued)
FLASHMEDIACMD1
BITS
FIELD NAME
RW
MEANING
RES
NOTES
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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