Hello.
I have STM3H723ZG Nucleo, by pulling boot pin high and providing reset condition, Nucleo stays in system bootloader mode.
With Slave select low, I am send sync byte ( 0x5A) connections made over SPI3 port of STM32H7 controller form my Host controller and successfully receiving ACK (0x79) from STM controller and after receiving ACK from STM32H7 sending ACK (0x79) from host controller to STM32H7 and pulling Slave select in high state.
As stated in application notes AN4286
https://www.st.com/content/ccc/resource/technical/document/application_note/7a/8a/0a/8f/8f/38/47/c0/DM00081379.pdf/files/DM00081379.pdf/jcr:content/translations/en.DM00081379.pdf
STM32H7 controller is now sync in SPI3 boot mode, but after this procedure on pulling slave select again LOW for sending commands to STM32H7 in order
- 0x5A
- command ( 0x00) GET command
- command check sum (0xFF)
and again sending 0x00 as dummy bytes for receiving STM32H7 response, I am getting NACK (0x1F) after some tries for the first time, but not ACK from STM32H7.
On getting NACK I am again pulling HIGH and LOW to slave select and sending GET command with slave select in LOW state, and trying to receive ACK , but not getting ACK nor NACK in this case.
I would like to know whether to use Slave select in system programing in boot mode or not.
second, if am getting ACK in the procedure of boot sync , how to get the same while sending command ?
An sample code to flash system memory in SPI mode would be great help.
I have debugged by SPI data over analyzer , i am sending correct byte to STM32H7 but still not getting ACK from STM32H7.
