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LMK5B12204: regarding the I2C block read operation

YONG HOON KIM
Prodigy 100 points
Part Number: LMK5B12204

Hello,

I like to know the block read operation of this LMK5B12204.

I tried block writing operation and it seems to be done successfully.

But for the block reading, it can only get the first byte data successfully and the other data read with 0xFF.

The following captured image is from the block read operation for the first two registers from address 0x0000.

It seems to me that the captured image satisfies the data sheet, but if you have any thought on this, please let me have them.

Thank you.

  • 0
    TI__Mastermind 28540 points

    Hello,

    Is an update by Friday on this acceptable?

    73,
    Timothy

  • 0 in reply to Timothy T
    Prodigy 100 points

    Hello,

    Thank you for your reply, but I couldn't catch the context fully.

    So, I think it's better to explain the issue more detail.

    I used two bytes address mode access as the datasheet guides.

    I can read the first 8 registers from 0x0000 address with single register access illustrated at page 59, "Figure 9-36. I2C Byte Write and Read Transfers" as following.

    0x10,0x0B,0x35,0x42,0x19,0x0B,0x15,0x11

    I think those readout look like corresponding to the values in the datasheet.

    But when I tried to read those registers with block mode as in "Figure 9-37. I2C Block Register Transfers", then the readout values go as follows

    0x10,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF

    And there were no errors in I2C communications even in this block mode access.

    The image at the above was to show the timing and ack response when block mode readout of only two registers from 0x0000.

    Thank you

  • +1 in reply to YONG HOON KIM
    TI__Mastermind 28540 points

    Hi,

    I've checked against a block read I did in my lab, it seems you are not sending an ACK bit after first read.  I imagine this is aborting the read.  Seems this can/should be high for when you're done - after the second byte in this case.

    73,
    Timothy

  • 0 in reply to Timothy T
    Prodigy 100 points

    Hello, Timothy.

    Thank you for the help in detail.