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MicroSD SDHC card and SPI initialization

I have a Kingston SDHC 32bit microSD card which needs MSP430F2618 via SPI . I could not initialize it using CMD55 + ACMD41 (with bit30 set to 1), as described in the specification specification SD. What works in this sequence:

  CMD0, arg: 0         , CRC: 0x95 (response:0x01)
  CMD8, arg: 0x1AA     , CRC: 0x87 (response:0x01)
  CMD1, arg: 0x40000000, CRC: 0xFF (response:0x00)

I tried it also with an 8 inch SanDisk card and worked for that too. In fact, I use CMD1 here, not ACMD41, with the HCS bit set to 1. However, it is not stable, sometimes it works, sometimes it is not. This may be due to equipment.

Isn't it strange that cards react to CMD1 with an argument 0x40000000?

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CMD1 SDHC; SD-:

CMD1 , MultiMediaCard SD.

( , ) IDLE, CMD1. CMD8 0x1AA reset (CMD0), CMD55 + ACMD41.

tl; dr , :

  • CMD0 arg: 0x0, CRC: 0x95 (: 0x01)

  • CMD8 arg: 0x000001AA, CRC: 0x87 (: 0x01)

  • CMD55 arg: 0x0, CRC: any (CMD55 ACMD)

  • ACMD41, arg: 0x40000000, CRC: any

  • : 0x0, ; 0x1, goto 3.

, 3/4, , CMD0/CMD8/CMD55/ACMD41/CMD55/ACMD41 - , n ( n ) , , .

, , SS (aka CS) CMD0 - , , , SD-.

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