Two board I2C communication

[Adi3]

Iam Using 2 STM32F407VGT6 board one as master and another board as slave from Master side it is Transmitting but slave is showing the Bus error both Master and slave iam using in the inturrept mode  

[Ghofrane GSOURI]

Hello @Adi3 

Make sure the hardware connections between the two STM32F407VGT6 boards are correct, including proper wiring of communication lines and the presence of required pull-up resistors  using I2C. Ensure both master and slave are configured with matching clock speeds and that the slave address matches the master's target address. Make sure the interrupt service routines properly handle and clear all relevant flags, especially the bus error (BERR) flag on the slave, to prevent persistent errors. Finally, use debugging tools to step through interrupt handlers and confirm the communication protocol is correctly working.

THX

Ghofrane

[Andrew Neil]

Are you using the "I2C Two Boards" example provided by ST ?

If not, try that to start with.

See also: https://wiki.st.com/stm32mcu/wiki/Getting_started_with_I2C

As @Ghofrane GSOURI said, check your connections & pullups carefully - make sure you also have a common ground between the two boards.

Show your schematic, and some good, clear photos of the setup.

Have you used an oscilloscope or analyser to see what's happening on the I2C wires?

The trouble with using 2 boards like this is you don't know which end has the problem - or if both ends have problems!

See:

https://community.st.com/t5/stm32-mcus-boards-and-hardware/i2c/m-p/668411/highlight/true#M18743

[Adi3]

when i changed the handler of slave I2C to I2C1 to I2C2 then that bus error is not showing insted of that it is showing an unknown error 0x0 error code i have given slave address 0x12

[Andrew Neil]

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@Adi3 wrote:

i changed the handler (sic) of slave I2C to I2C1 to I2C2 

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Did you mean handle there - rather than handler ?

So was it working before you made that change ?

If you changed from using I2C1 to using I2C2, did you also change the pin configurations to match?

Did you check that those pins are free on the board?

Have you used an oscilloscope or analyser to see what's happening on the I2C wires?