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LMK04828: Read sequence

Part Number: LMK04828


Hello, I am trying to understand the SPI -3 wire timing diagram. 

For a read command is the command automatically latched into the shift register after the 16th bit with the read data then being available for the next 8 clock cycles on the SDIO pin? or does a full 24bit command need to be sent followed by asserting CS followed by an additional 8 clock cycles to read the data?

An example of a read sequence would be nice.

Thank you.

  • I found this answer from Tim in another thread:

    "The readback should be able to be accomplished using a single transaction.
    Clock R/W = 1; W1 & W0 = 0. Address as desired. Then flip your SDIO line for input, and then provide the next 8 clocks for data."

    "So after writing the R/W (as 1), W0/W1 (as 0), then the address, the state for your masters IO pin will change to either tri-state or pull-up. Note that SDIO_RDBK_TYPE = 0 (pushpull) or 1 (open drain output -- requires external pull-up from PCB or master)."

    Link: e2e.ti.com/.../428788

    Kind regards,
    Lane