Command for SD/MMC card
- CMD0, GO_IDLE_STATE, Reset all card to idle state.
- CMD1, SEND_OPERATION_CONDITION, (MMC/Thin SD Card vaild), SD has a ACMD41 a same funciton.
- CMD2, ALL_SEND_CID, Asks any card to send their CID numbers on the CMD Line.
- CMD3, SEND_RELATIVE_ADDRESS,
- CMD5, IO_SEND_OPERATION_CONDITION, in SDIO Specification
- CMD15, GO_INACTIVE_STATE,
- CMD55, APP_CMD,
- ACMD41, SD_APP_OP_CONDITION, SD Applicaiotn Operation Conditions.
SD Memeory Card basic command CMD0, CMD15, CMD55, CMD41, CMD8(ver 2.0)
SDIO Card basic command CMD0, CMD5, CMD55, CMD41
- R1, Length : 48bit, Normal response
- R1b, Length : 48bit, same R1, but added card busy status
- R2, Length : 136bit, but only read 128bits on Mainstone platform (CID or CSD register)
- R3, Length : 48bit (OCR register value)
- R4, Length : 48bit, SDIO_OP_CONDITION, Reverse SDIO Card
- R5, Length : 48bit, IO_RW_DIRECTION, Reverse SDIO Card
- R6, Length : 48bit (RCA register)
- R7, Length : 48bit (interface condition, VHS(voltage supplied), check pattern, CRC7)
Currently a detect card type flow chart in Simplified SDIO Card Specification v2.0.
Card initialization delay maximum 1mili second (least 74 Clock, CS and CMD signal should keep up High level, Normal SD Host controller implement 80 clock)after Power up.after can send first command to card.
Simplified SDIO Card Specificaiton v2.0
Simplified SD Physical Layer Specificaiton v2.0