2013-07-08 07:34 AM
Hi,
we want to use the STM32F106RCT6 in our Future Products. So we Build an prototype an all works fine except the USB DFU Bootloader. We plugged the USB Cable in and the PC didnt recognize the Device. The Markings on the Chip STM32F107 RCT6 990RG 93 MYS 99 031 We wired the Vbus on PA9, an rest of USB also, BOOT0 = 1,BOOT1=0 After the Reset nothing :o Whats wrong with these Chips? Have we forgot something? Master of Engineering Sebastian Mueller2013-07-08 08:08 AM
Have we forgot something?
Probably, DFU works fine on a Z step STM32F107VCMIC Z 990WA 93 MYS 99 947''The system clock is derived from the embedded internal high-speed RC for USARTx bootloader. This internal clock is used also for DFU and CAN bootloaders but only for the selection phase. An external clock (8 MHz, 14.7456 MHz or 25 MHz.) is required for DFU and CAN bootloader execution after the selection phase''2013-07-09 12:40 AM
We using an external 25Mhz Crystal and i have read the AN2602, but we cant get this to Work...
The Revision Z, i thought we got one , there an small ''Z'' next to the ARM Symbol Master of Engineering Sebastian Müller2013-07-09 04:30 AM
Consider this a working, reference design.
http://www.st.com/st-web-ui/static/active/en/resource/technical/document/user_manual/CD00246066.pdf
2013-07-09 08:51 AM
Did you connect PA9 directly to VBus or via a resistor? There is a problem in some revisions of the chip where pin PA9 is configured as ''output'' by the bootloader and thus will not recognize VBus unless you have a quite potent supply (about 50mA I think, definitely more than the absolute maximum ratings in the datasheet).
I think it has been discussed in a forum thread here, and possibly also in the Errata document. HTH jens2013-07-09 08:55 AM
Also see:
https://my.st.com/public/STe2ecommunities/mcu/Lists/cortex_mx_stm32/Flat.aspx?RootFolder=https%3a%2f%2fmy.st.com%2fpublic%2fSTe2ecommunities%2fmcu%2fLists%2fcortex_mx_stm32%2fSTM32F105%20PA9OTG_FS_VBUS%20Issues&FolderCTID=0x01200200770978C69A1141439FE559EB459D7580009C4E14902C3CDE46A77F0FFD06506F5B&c...