UART Communication with e paper display fails

[eegdemir]

Hello Guys,

I am using waveshare 4.3 inch e paper UART display module. I looked to manual thousand time and I found a library called epd. this library was written in cpp and I rewrote for my stm32f411RE nucleo board in c and HAL Library. Buffer working good and I am transmitting hex codes to my computer. But the screen doesn't respond to these commands. I need for your help. My files and displays wiki are attached.

Thank you!!

 

https://www.waveshare.com/wiki/4.3inch_e-Paper_UART_Module 

 

 

 

[Tesla DeLorean]

Not sure there are a lot with the hardware to do the debug for you.

The IsSend will need to be volatile if changed in interrupt/callback.

Perhaps add diagnostic / telemetry output via serial so you can observe the interactions between the STM32 and display. Use a scope or logic analyzer to check the hardware level interactions.

[eegdemir]

Thank you for your answer!!

I am sending data to display via USART2 which connected both pc and display and I observed the data that board send to display. At the pc side everything fine but display doesn't respond. 

wiki says there is a parity bit but it is in the library. should I set a parity bit by cube mx? but I don't know how to set that because wiki doesn't say what parity is that (odd or even).

[AScha.3]

You can try it - just set (in cubemx) in usart2  parity , then try.

If still no response, change odd/even and try again.

[Pavel A.]

Here you can get help with this.