AnsweredAssumed Answered

SD card init issue

Question asked by Anthony SIEGRIST on Sep 21, 2018
Latest reply on Oct 1, 2018 by CarlosCasillas



In some cases, UHS-I card are not communicating with the right timming. This bug is present is SDK 2.4.2.


To reproduce the bug:

1. Initialize with UHS-I card inserted, bus speed goes to kSD_TimingSDR104Mode=> OK

2. Remove the UHS-I card and insert an non UHS-I card, bus goes to kSD_TimingSDR25HighSpeedMode => OK

3. Remove the non UHS-I card and insert an UHS-I card, bus goes to kSD_TimingSDR12DefaultMode => NOK


Because "currentTiming" is not reset to kSD_TimingSDR12DefaultMode, the init sequence does not work as expected.

My fix is reset card->currentTiming to kSD_TimingSDR12DefaultMode  in fsl_sd.c.




status_t SD_CardInit(sd_card_t *card)

    uint32_t applicationCommand41Argument = 0U;

    if (!card->isHostReady)
        return kStatus_SDMMC_HostNotReady;
    /* reset variables */
    card->flags = 0U;
    card->currentTiming = kSD_TimingSDR12DefaultMode;
    /* set DATA bus width */
    /*set card freq to 400KHZ*/
    card->busClock_Hz = SDMMCHOST_SET_CARD_CLOCK(card->host.base, card->host.sourceClock_Hz, SDMMC_CLOCK_400KHZ); 
    /* send card active */
    SDMMCHOST_SEND_CARD_ACTIVE(card->host.base, 100U);
    /* Get host capability. */
    GET_SDMMCHOST_CAPABILITY(card->host.base, &(card->host.capability));