I have been trying to get my development environment working again. During development of the timers en battery backed sram i used the ST-Link V2 clone to flash the STM32F407 in my software. I could not use the USB port for anything as the usb port told me the "USB enumeration failed"
The PCB of the black STM32F407VET6 boards have a hardware design flaw! I noticed a 1.5k pull up resistor [R21] to the 3.3 volt in the schematic. This enumerates the device on the USB port before the device is booted and can respond to the host (computer). The stm32F4 have this resistor in the MCU itself so no need for an external one. So to get the USB working remove the R21 resistor from the board. Now USB works! (Also USB serial just like the arduino mega)
Now if you use the arduino IDE with STM32duino core and the install the STM32CubeProgrammer software
https://www.st.com/content/st_com/en/pr ... eprog.html
You can download the speeduino firmware to the STM32F407 black
1. putting the jumper BT0 on position 1 (slide it to the 3.3volt rail) .
3. Plug the device in an USB port
4. Reset the device.
5. Arduino IDE select Board: GENERIC STM32F4 series
6. Arduino IDE select Board part number: "BLACK F407VE"
7. Arduino IDE select Programmer: "STM32CubeProgrammer DFU"
8. Press upload
Ow and first debug the compiling errors. But that is something for tomorrow.