2023-09-29 09:01 AM
Hello.
I buy board STM32F401Development Board V3.0 STM32F401CCU6 .
Board workin and work usb, but me need can bus.
I replase SMM32F401 MCU on STM32F105RCT6.
Board work and programming bun not work USB ((. DFU mode not work.
I searching difference USB between SMM32F401 and STM32F105. Not found ((.
Please help do work USB on STM32F105.
Solved! Go to Solution.
2023-10-06 05:21 AM - edited 2023-10-06 05:21 AM
One more difference: 'F105 requires VBUS (+5V from USB, possibly divided down to 3V to reduce risk of damage) to be connected to PA9; whereas 'F401 does not require that, so it's probably not connected on the board.
Read relevant chapters in AN2606.
JW
PS. Don't be scared by the datecode 937 issue - as there's only one digit for year in the datecode, this (from context) means chips made in 2009 week 37 and older, i.e. from the first batches of STM32. It's unlikely you have those.
2023-09-29 09:07 AM
It would surprise me if it were a drop-in replacement, double check pins and power.
Pull Data Sheets for both and walk the pin lists.
2023-09-29 11:03 AM
I watched. There are no differences.
Show at least one difference in USB
2023-10-02 12:22 AM
stm32f105rc
2023-10-02 12:25 AM
STM32F401CCU6
2023-10-03 12:43 AM - edited 2023-10-03 12:44 AM
What crystal is on the board?
JW
2023-10-05 05:46 AM
Instaled 25 MHz.
I changed it to 8MHz, still doesn't work.
And what does crystal have to do with it if the STM32F401CCU6 works. STM32F401CCU6 also requires crystal!
2023-10-05 07:44 AM
> And what does crystal have to do with it if the STM32F401CCU6 works. STM32F401CCU6 also requires crystal!
Yes, but 'F401 DFU bootloader can work from a much wider selection of crystals.
I don't quite understand how did you use a QFP-64 chip ('F105RCT) on a QFN-48 board ('F401CCU).
JW
2023-10-05 09:26 AM
2023-10-05 09:31 AM
STM32F105RCT6 with crystal 25MHz