I am working on an STM32f401 Nucleo board(datasheet for reference: http://www.kynix.com/uploadfiles/pdf65976/STM32F401CCU6.pdf) and ESP8266-01 wifi module.
I am using Eclipse gcc-arm tool chain and cubeMx to generate code. I can transfer and receive data perfectly with USART/UART DMA.
Now I am stuck with ESP8266-01. I cannot send data from MCU to ESP and I'm not getting response from ESP to MCU. I already tested the ESP module communication, I can connect TO THE wifi with AT commands through USB and can also receive data in web via socket connection.
BTW，I configured USART1_TX/USART1_RX with PA9/PA10
Well i had the same problem for the evaluation boards , but didnt yet quite find the solution that i wanted.
[Link to supplier removed]
Just for clarity there is no issue with an STM32F401 serial
So, perhaps look to code, or compiler
Perhaps see Manufacturer's Datasheets, Reference Manuals and Appnotes.
Solutions aren't found, they are made with code.
and what has this to do with a Nextion HMI display?
if your communication between a STM and an ESP won't work, you should rather ask on either STM or ESP developer forum ...