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
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 ...