STM32F405 usb recognization

erdemkose78 · ‎2014-05-20

Posted on May 20, 2014 at 13:39

we've made an oscilloscope that displays data on PC screen with a software,which is creted on Qt Creator. The MCU software works well on STM32F4 Discovery board,which has STM32F407VG; but when we program STM32F405RG,program loads successfuly, device manager of Windows says ''device not recognized'', but Windows sees the device. We draw the pcb parts based on ST schematics. What is the difference between 405RG and 407VG? What may be the reason of this problem?

chen · ‎2014-05-20

Posted on May 20, 2014 at 14:00

Look like the number of pins - which then affects the pin outs

http://www.st.com/web/catalog/mmc/FM141/SC1169/SS1577/LN1035

(check the table - RG is 64 pin VG is 100pin)

sdim · ‎2014-05-21

Posted on May 21, 2014 at 12:45

Step 1: Check the clock settings.

Do they match your board?

You must set the correct HSE_VALUE and multiplier values (PLLM,PLLN, etc).

Run an example of the STM32 USB library 2.1.0 (25Mhz crystal default, modify it for your board) to test it.

Step 2: Check the device descriptor. Just one wrong byte on the device descriptor can cause this problem.

Step 3: If you use a custom VID/PID, you must write your own driver. In simple cases like VCP, an inf file is all you need.

Step 4: If you use a hand-written driver, you may miss some packets on endpoint 0.