DORHEA 3Pcs STM32F411 Development Board V3.0 STM32F411CEU6 STM32F4 Learning Board 100Mhz Freq 128KB RAM 512KB ROM for Ardu-ino Programming

These things are great. Basically a small Arduino board with a 32 bit ARM processor. ST provides a suite of tools to work with the processors. They can run most standard C code without modification, and generally faster than traditional 8 bit Arduinos. There is much computing power with relatively few IOs, but they are capable of many communication protocols, so it is easy to add expansion boards or additional processors.They have an arithmetic unit, meaning they have hardware to do float point and other math that is not directly supported by the ARM architecture.

These are advertised as hosting F411 processors, but the chips on the 3 I received are F401CEU6. Of course I realized that after soldering on SWD headers - by the way only 1 of the 3 boards had a 4 pin header in its antistatic baggie. Not a deal breaker, I've got plenty in the parts pile. All of the of the 3 board's MCU chips are scratched and scuffed, but 1 is cracked. It still communicates with ST Link, erases (after clearing the readout settings) and ultimately programs and verifies fine. However I can't get a simple blink sketch to work on the user LED let alone any more complex code on any of the 3. That's enough for me to decide that I will suffer the shipping delay and stick with genuine WeAct Studios boards. This is a hobby so if something makes me stress out it's not worth the price paid - YMMV.

I purchased these boards for the large 512KB FLASH memory size, due to my project outgrowing the Blue Pill memory. There are a number of versions of the STM32F411 chip, with varying amounts of FLASH, but this board was advertised as having 512KB. On loading the device in the STMCubeIDE, it was reported as only having 128KB of FLASH. So it appears the chip isn't as advertised.