SanDisk SD Card

Revision 2.2Chapter 4 – SD Card Protocol DescriptionSanDisk SD Card Product ManualCMD Index Type Argument Resp. Abbreviation DescriptionCMD43CMD51…ReservedApplication-specific Commands (Class 8)CMD55 ac [31:16]RCA [15:0]stuff bitsCMD56 adtc [31:1] stuffbits [0]RD/WRCMD58-CMD59CMD60-CMD63ReservedI/O Mode Commands (Class 9)Reserved for manufacturerR1 APP_CMD Indicates to the card thatthe next command is anapplication-specificcommand rather than astandard commandR1 GEN_CMD Used either to transfer adata block to the card orto get a data block fromthe card for generalpurpose / applicationspecific commands. Thesize of the data blockshall be set by theSET_BLOCK_LENcommand.RD/WR: “1” the hostgets a block of data fromthe card. “0” thehost sends block of datato the card.All the applicationspecificcommands aresupported if Class 8 isallowed (mandatory inSD Card).CMD52…CMD54Reserved for I/O mode (refer to SDIO Card Specification.Switch Function Commands (Class 10)CMD6 adtc [31] Mode 00:Check function1:Switch function[30:24] Reserved (all 0)[23:20] Reserved for functiongroup 6 (all 0 or 0xF)[19:16] Reserved for functiongroup 5 (all 0 or 0xF)[15:12] Reserved for functiongroup 4 (all 0 or 0xF)[11:8] Reserved for functiongroup 3 (all 0 or 0xF)[7:4] Function group 2 forcommand system[3:0] Function group 1 foraccess mode.R1 SWITCH_FUNC Checks switchablefunction (mode 0)and switch cardfunction (mode 1).CMD34CMD35CMD36CMD37CMD50Reserved for each command system set by switch function command (CMD6). For detaileddefinitions, refer to each command system specification.© 2004 SanDisk Corporation 4-36 12/08/04