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TM4C1237E6PM: USB Supported class

Part Number: TM4C1237E6PM

Hi community,

What is the USB classes supported by TM4C1237E6PM microcontroller ?

Is this micro controller supports CDC Class ?

Thanks & regards,

Divya

  • Hello Divya,

    That MCU can support many USB classes including but not limited to CDC, HID, MSC, Bulk, and Audio which all are supported via TivaWare usblib.

    Our TivaWare example for CDC can be viewed at [Install Path]\TivaWare_C_Series-2.1.4.178\examples\boards\dk-tm4c123g\usb_dev_serial
  • Hi,

    Thanku for clarifying the USB classes on TM4C MCU.

    I need some clarification regarding the MCU operating mode & USB functionality.

    1)When system does not have any battery (backup supply), then what may be VBAT pin state ? Needs to be shorted with VDDA/VDD ? Hibernate oscillator pins (XOSC0 , XOSC1) ? HIB pin and WAKE pins ?? need to be made as NC ??

    Please help me find the solution.

    2)As per the TM4C design guidelines VBUS & ID pins are not 5V tolerant at power up and reset state,  then how can i build the circuit at power up ?

    Thanks & regards,

    Divya

  • Hello Divya,

    For question 1, see Table 21-7 in Section 21.6 of your device datasheet for a table summarizing how to connect unused pins: www.ti.com/.../tm4c1237e6pm.pdf

    For question 2, design is up to you and what resources you have available. First idea off the top of my head is a tristate, but there are probably more elegant solutions.

    An interesting note I had found on E2E from one of our prior device experts who knew USB better than I is that it is permissible to apply 5V to the VBUS pin when power ramping: e2e.ti.com/.../2079165 - this aligns with our LaunchPad design which does not have any circuitry to prevent VBUS from having 5V applied before power up as well. However, it does contradict the design guidelines (I didn't write that document or design our LaunchPad), so I would still say following design guidelines would be best. Just wanted to inform that there seems to be precedent that there is no extra circuitry needed...
  • Hi,

    Thank u for the support.

    Still i am having the below queries regarding OTG mode of operation.

    what is the input High Voltage level on ID pin ? 3.3V or 5V ? 

    Thanks & regards,

    Divya

  • Hello Divya,

    USB0ID is a 3.3V signal.
  • Hi ,

    Thank for the reply.

    Also please help me to find out the answer for the below query.

    what is the SPI clock frequency of TM4C1237 micro controller in master mode of operation ?

    Thanks & regards,

    Divya

  • Hello Divya,

    The SPI clock frequency is configurable. I would recommend making a new post if you need help understanding how to configure the SPI clock with TivaWare API's.