A 26 MHz clock speed in the context of eMMC (Embedded MultiMediaCard) refers to a legacy transfer mode (Single Data Rate or SDR) where the eMMC device communicates with the host at a slower speed.
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In eMMC communication, a 12mA drive strength is often specified for signal lines like EMMC_CLK, EMMC_DATA, and EMMC_datastrobe to ensure proper signal integrity and reliable data transfer,