USB CDC Port Not Shown In Device Manager(MCU STM32F!103RET6)

[Smit Italiya]

Hello Everyone,

Right now i am facing the issue on detection USB.I am attaching snap shots of the my USB configuration.

USB port not shown after powering up the board. i am doing some basic thing like on receiving via USB in RX interrupt function of USB i set one flag that will used in main function for further process.

Help Me if anyone knows the issue, i stuck here since 2 days.

STMCubeIDE Version:- 1.13.2

MCU:- STM32F103RET6

Debugger:- Jlink(4000Khz)

USB DP:- PA12

USB DM :-PA11

Internal Power Supply used which is given to MCU and other board peripheral.

[Smit Italiya]

Thnaks you so much AScha.3, as you suggest pull up of 1.5k on DP pin it works for L0 series not in F1 series but its fine we need 100 pins and L0 is compatible with out requirements 

[Smit Italiya]

Thank you So much for helping me out with this problem i increase heap and stack size with pull of 1.5k on DP pin and additionally pull down of boot pin is needed all works for L0 series we needs to find what was the problem with the F1 series but at last i am able to communicate via usb. MCU:-STM32L073RBT6

[gbm]

The 1k5 pullup is NOT needed for L0 series. Search for some real hardware problem if adding the resistor improved the situation - it masked the real problem, not solved it.

[Smit Italiya]

Yes you're right and we will real problem asap i think this is the Temporary solution but it works for 2 L0 board.as of now we switch to L0 and we will find real problem by trying other combinations and debugging hardware

[Piranha]

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@Smit Italiya wrote:

can you explain me more about what your point of view because i am not able to understand properly i am slightly new to USB

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That is not a "point of view", but a concrete code with issues explained. If you don't understand, then you have to start with learning the basics. You are not new to USB, you are new to everything in microcontrollers. And you are not slightly new, you are an absolute beginner.

https://www.embeddedrelated.com/showarticle/453.php