1 Reply Latest reply on Oct 9, 2018 12:18 AM by sanm

    Do I need to have non-default firmware to support RID emulation for an ACA-Dock application?

    jonathanlui_3455101

      Hi,

       

      Cypress has a demo board for ACA-Dock application that pairs the PSoc4 with the HX3 USB3.0 hub. The purpose of the PSoC4 is to emulation different resistor values for RID:

      http://www.cypress.com/documentation/other-resources/hx3-and-psoc4-based-aca-docking-solution

       

      I have two more-specific questions in regards to this setup:

      1. What kind of resistor values can the default PSoC4 firmware support/emulate? How do I select a particular value?

       

      2. There is a note somewhere that says if additional proprietary resistor values are needed, I would need to update the PSoC4 firmware. How do I do this (i.e. which function call do I use in which section of the code)?

       

      Thanks,

      Jonathan

        • 1. Re: Do I need to have non-default firmware to support RID emulation for an ACA-Dock application?
          sanm

          Hi Jonathan,

           

          1.The PSoC4 firmware gives no limitations on the resistor values and you can select the RID value based on the requirement of the device on the upstream port. You can simulate the RID value by either increasing the current across a lower resistance for the appropriate voltage drop across RID pin or use a multiplexer to choose between the physical resistances.

          2. If you are using a physical resistor, you can use a multiplexer to choose the appropriate value and make changes to your main function which calls the Select function of the multiplexer.

           

          Best Regards,

          Sananya