STM32L USB Driver for Keil

A good day to all,

does anybody know about an USB low level driver file for the Keil lib on STM32L chips?

Unfortunately Keil supports - up to now - only the F-Types in full and high speed.

The ones I find are:

usbd_STM32F103.c
usbd_STM32F10x_cl.c
usbd_STM32F2xx_FS.c
usbd_STM32F2xx_HS.c
usbd_STM32F4xx_FS.c
usbd_STM32F4xx_HS.c

thanks in advance,
Uli

Parents
  • The USB device engine on STM32L is almost same as STM32F103.
    The only difference is the D+ pull-up resistor: STM32L has on-chip pull-up.
    But this pull-up isn't compliant to the USB spec, as this errata tells, on all revision.

    STM32L15xx errata sheet
    www.st.com/.../CD00278726.pdf
    2.5.1 Pull-up resistor has a value lower than 1.5kOhm
    Description: The pull-up resistor on USB line is requested to have a nominal value of 1.5kOhm, whereas the characterization of the internal pull-up shows a value between 0.81 and 0.95 kOhm o the full temperature range.
    Workaround: An external pull-up resistor controlled by a GPIO can be used.

    After all, STM32L requires an external pull-up resistor. In this configuration, there is no difference from STM32F103.

    Therefore, you may start with usbd_STM32F103.c for STM32F103

    Tsuneo

Reply
  • The USB device engine on STM32L is almost same as STM32F103.
    The only difference is the D+ pull-up resistor: STM32L has on-chip pull-up.
    But this pull-up isn't compliant to the USB spec, as this errata tells, on all revision.

    STM32L15xx errata sheet
    www.st.com/.../CD00278726.pdf
    2.5.1 Pull-up resistor has a value lower than 1.5kOhm
    Description: The pull-up resistor on USB line is requested to have a nominal value of 1.5kOhm, whereas the characterization of the internal pull-up shows a value between 0.81 and 0.95 kOhm o the full temperature range.
    Workaround: An external pull-up resistor controlled by a GPIO can be used.

    After all, STM32L requires an external pull-up resistor. In this configuration, there is no difference from STM32F103.

    Therefore, you may start with usbd_STM32F103.c for STM32F103

    Tsuneo

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