SD card init issue

o00batman00o — Fri, 21 Sep 2018 11:29:20 GMT

Hello,

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)
{
    assert(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 */
    SDMMCHOST_SET_CARD_BUS_WIDTH(card->host.base, kSDMMCHOST_DATABUSWIDTH1BIT);
    /*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));
...‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Re: SD card init issue

CarlosCasillas — Mon, 01 Oct 2018 21:25:03 GMT

Hi Anthony.

Thanks for sharing your solution with the Community!!

Best regards!

/Carlos

topic SD card init issue in i.MX RT Crossover MCUs

SD card init issue

Re: SD card init issue