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DLP4710EVM-LC: DLP4710EVM-LC-I2C

MarkCh
Prodigy 70 points
Part Number: DLP4710EVM-LC
Other Parts Discussed in Thread: DLP4710, , DLPC3479

Hello,

I have a few questions regarding connecting a microcontroller to DLP4710 and trying to communicate over I2C.

- From the schematics it looks like that I need to short/put 0 ohm resistors on R177 and R178 to connect to J11 for I2C communication. Is this correct?

- Do I need to change the functionality of SW21 by pressing and holding it?

- If the I2C channel is a multimaster bus with the Cypress and MSP430 as the masters, do I need to connect a microcontroller that supports multimaster or just a normal microcontroller such as an arduino would be fine? How does this would work? Would MSP430 still function as a master? Could you please elaborate? 

Thank you for the help.

  • 0
    TI__Expert 7105 points

    Hello MarkCh,

    Please allow us some time to get back to you.

    Best,

    Maximus

  • 0 in reply to Maximus Rusi
    TI__Expert 7105 points

    Hello MarkCh,

    I would recommend the following

    • Remove R487, R151, R537, R538
    • Install R177, R178 (0 ohm)

    This will allow you access to the I2C bus without the MSP interrupting but without having to reconfigure SW21.

    Best,

    Maximus

  • 0 in reply to Maximus Rusi
    Prodigy 70 points

    Dear Maximus,

    Thank you for your reply. I will do these and get back to you.

    Could you please elaborate on how to reconfigure SW21? I saw the following statement on the user's guide for DLP4710EVM-LC, but not sure how it can be accomplished. 

    D67  STAT_LED0 LED  blinking when PC is communicating to DLPC3479 over I2C

    Thank you,

  • 0 in reply to MarkCh
    TI__Expert 7105 points

    Hello MarckCh, 

    The setup I recommended does not require SW21 to be reconfigured at all. Currently the MSP430 polls SW21 and will startup/shutdown the DLP chips according to the button press. The method I recommended removes the MSP430 from the I2C bus but allows it to still poll SW21 for startup/shutdown purpose. If you would like to repurpose it, that will depend on your intentions for the it.

    Best,

    Maximus

  • 0 in reply to Maximus Rusi
    Prodigy 70 points

    Dear Maximus,

    Thank you for your response.

    The issue that I am facing is that removing the MSP430 from the I2C bus will prevent accessing the HDMI controller (which I need). By probing the I2C pins, I can also see that the MSP430 is constantly communicating with that slave. I do not want to get rid of the MSP430.

    From the MSP430 code, I can see that there is an MSP slave I2C connection. This will potentially allow the I2C commands to be sent over to the DLPC. Are there any documentations about this and connecting a master I2C MCU to the external I2C header?

    Thank you,

    Best,

  • +1 in reply to MarkCh
    TI__Expert 7105 points

    Hello MarkCh,

    The DLPC does not support a multi-master I2C bus. There must only be one master at a time so if you would like the MSP to still perform it's functions in terms of monitoring HDMI signal, I would recommend editing the provided MSP code to fit your application. The MSP source code can be found on the EVM product page (link).

    Best,

    Maximus