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LM98714 Initialization code

Hi Members.

I am new to LM98714

so pls help me to initialise LM98714,

Am trying to initialise the device in CMOS mode and with out CCD timing generator, my INCLK is 50Khz.

Regards

Govind Raj

  • In reply to Prasanna Ganapathi:

    Hi Prasanna,

    The active register page (5 total) is denoted by the value of register 1Fh three (3) LSB bits. This register is mirrored on all register pages.

    So, when you read back the register address / value, you must also refer to the content of register 1Fh to see which register page the data belongs to.

    The LM98714 register read should yield 5 bits of address and 8 bits of data per datasheet Figure 62. So, I'm not sure what you mean when you say the "register dump" because that is not a LM98714 function but rather relates to the tool you are using to read the LM98714 register contents. Therefore, I think this is an exercise in "deciphering" the dumped values by keeping track of the Page number from register 1Fh.

    Please let me know if I've not answered your question properly?

    Regards,

    Hooman

  • In reply to Hooman Hashemi:

    Hi Hooman,

    I was referring to "5621.LM98714.txt" file you shared in earlier post. It has register address from 0x0 to 0xBF.

    Is there any specific sequence for register programming.

    Regards

    Prasanna

  • In reply to Prasanna Ganapathi:

    Hi Prasanna,

    You must be referring to this file which I posted earlier:

    This file was generated by the SensorEval tool (image below) with file extension changed to *.txt:

    Here is a thread that includes the SensorEval installation file:

    Note: Using SensorEval with LM98xxx Imaging devices with Windows versions beyond Windows xp is limited to monitoring the register / device states. You cannot use this tool to read / write the LM98xxx device registers as it is not fully compatible with Windows 7, etc.

    The register address in the file combines the 5 bits of address that the chip has, with the page address setting used to create the upper bits.

     Here are some examples of different Page/Register value combinations as they would appear in the register file.

     

    Page Binary (0 to 5 decimal)

    Register Binary (00 to 1F hex)

    File Address Binary

    File Address Hex (00h to BFh)

    000

    0 0000

    0000 0000

    00h

    000

    0 1000

    0000 1000

    08h

    001

    1 1000

    0011 1000

    38h

    010

    0 0010

    0100 0010

    42h

    011

    1 0100

    0111 0100

    74h

    101

    1 1111

    1011 1111

    BFh

     

    Hope this makes things clearer.

    Regards,

    Hooman

  • In reply to Hooman Hashemi:

    Hi Hooman,

    I have difficulty understanding the values of registers PIX1 Start, PIX1 End, PIX2 Start, PIX2 End, PIX3 Start, PIX3 End, PIX4 Start, PIX4 End (Page 2 address 0x7 through 0x11).

    What is the reference for start/end? ADC clock or Pixel clock or something else.

    A value of 1 in register is equivalent to how much pulse width?

    My mapping/connections are as follows

    PIX1 = CLK1 = CCD clock phase 1

    PIX2 = CLK2 = CCD clock phase 2

    PIX3 = CLK3 = CCD reset gate

    PIX4 = CLK4 = CCD clamp gate

    Regards

    Prasanna

  • In reply to Prasanna Ganapathi:

    Hi Prasanna,

    Sorry about the delay in getting back to you.

    Question: What is the reference for start/end? ADC clock or Pixel clock or something else.

    Response: The reference point for Start and End values is from pixphase (which can take on 4 different values) as shown below from page 77:

    Figure 19-21 also show this with timing diagrams for different operating modes

    As noted above, all Start and End timings are relative to pixphase. The value entered in the register is the measure of number of clock edges from pixphase. This is also shown in Figure 33-34 with timing diagrams.

    BTW, here is some additional detail not easily captured from the datasheet for your reference:

    For MODE3, PIXn start and PIXn end values can be from 0 to 41

    For MODE2, PIXn start and PIXn end values can be from 0 to 27

    For MODE1, PIXn start and PIXn end values can be from 0 to 13

    The max values above are doubled if the 1/2 frequency mode is enabled for that PIX generator.

    Regards,

    Hooman

  • In reply to Hooman Hashemi:

    Thanks Hooman. I am able to generate the clock pulses as per my sensor timing.

    Regards
    Prasanna