DEMO-AD5700D2Z HART_CLK connection

Hi,

This is regarding DEMO-AD5700D2Z board. I just started programming and evaluate the performance of the ICs in-order to zero in on them. I see that HART_CLK is connected to both P2.0 and P1.0. Can someone please explain me what is the reason to connect to two pins?

Also, on a custom board, I want to connect HART_CLK to just P1.0 as I want to use P2.0 and P2.1 as I2C lines. Is it feasible?

Thanks,

Spoorthy

ad5700 ad5700-1 hart demo-ad5700d2z

  • Hi Spoorthy,

    We are looking into this. We will get back to you.

    Thanks

  • Hi JB.Chua,

    Thanks for the reply.

    I'm sorry but I had to add another query. P2.2 is used for download push button. On a custom board, can I use P1.3 for download push button? (in order to use P2.1 as SDA line)

    Would I still be able to download code via CM3WSD?

    Thanks,

    Spoorthy

  • Hi Spoorthy,

    On the ADuCM360 microcontroller, P2.2 is dedicated to initialize UART download mode(held low during reset). You can not transfer this function to another pin. You have the option to not use the UART download mode. There is also dedicated serial wire/JTAG download and debug using pins 47 and 48.

    Please refer to ADuCM360 datasheet and user guide for more information:

    Datasheet

    User Guide

    Thanks

    JB

  • Hi Spoorthy,

    P2.2 is the only pin that can provide the UART download mode (as JB mentioned above), but you don't need P2.2 in order to use the I2C communications bus.

     I2C is actually available on 2 sets of pins, P2.0/P2.1 and P0.1/P0.2.  So if you need I2C communication you could use that other set of pins (P0.1/P0.2) and keep the connections to the HART_CLK as described in the CN0267.

    I'm not sure why the HART_CLK is connected to 2 sets of pins.  If you look at the pin functions, one is used as a potential UART Clock input (P2.0) and the other is an External PWM synchronization pin or External clock source (P1.0).  So perhaps in this application for the HART modem those functions are used in the software to do some application specific functions.

    Cheers,

    Brandon

  • Hi Brandon,

    Thanks for the reply.

    >P2.2 is the only pin that can provide the UART download mode (as JB mentioned above), but you don't need P2.2 >in order to use the I2C communications bus.

    Yes, I realized this. Sorry, my bad.

    >I2C is actually available on 2 sets of pins, P2.0/P2.1 and P0.1/P0.2.  So if you need I2C communication you could >use that other set of pins (P0.1/P0.2) and keep the connections to the HART_CLK as described in the CN0267

     

    But I need to use P0.1 and P0.2 for external UART in order to download code and analyse. I cannot invest on the J-link debugger right now as I cannot buy it separately, but only with Evaluation board of ADuCM360. Could you please let me know if there's a way to buy just the J-Link OB Emulator?

    >I'm not sure why the HART_CLK is connected to 2 sets of pins.  If you look at the pin functions, one is used as a >potential UART Clock input (P2.0) and the other is an External PWM synchronization pin or External clock source

    >(P1.0).  So perhaps in this application for the HART modem those functions are used in the software to do some >application specific functions.

    Could I configure P1.0 as potential UART clock input or do you foresee any problems by doing that?

    Thanks,

    Spoorthy