Stm32h755: hardware questions

[baselimadt]

Hi 

I am developing a board with two MCU on it (stm32h755), and I am going to programme these two controllers from the same connector using only two lines (SWDIO SWCLK), I have connected same CLOCK line to both MCUs directly, and the SWDIO to a switch to select which MCU to programme, is this connection fine??
Also this MCU has the CANFD, but I want to use normal CAN, is it fine to connect it to a normal CAN transceiver not CANFD one??.
thanks

[SofLit]

Hello,

To program more than one MCU you need a daisy chain configuration where serial debug does not support this feature according to this post. You can do it with JTAG, see this post.

For your last question, I didn't understand well your question. If you mean that you need to use a CAN transceiver 2.0A/2.0B transceiver with FDCAN interface, yes but you can't exceed 1Mb/s.

See this FAQ: https://community.st.com/t5/stm32-mcus/faq-can-i-use-a-can2-0a-can2-0b-transceiver-to-transmit-canfd/ta-p/689733

[baselimadt]

Hi Soflit.
to make it clear on the first question, I want to prgramme each MCU alone using STlinkv2, but both MCUs are sharing the clock line only and the data line is go to a switch to determine wich MCU to be connected with the STlinkv2.

and thanks you answered the second question I don't want to exceed 1Mb/s

[SofLit · Accepted solution]

SWCLK is an input to the MCU so you can share it with both MCUs: https://developer.arm.com/documentation/100893/1-0/Debug-and-trace-interface/Serial-Wire-Debug-signals