I2c1 problem at frequencies above 8MHZ

[Hossein Ghaheri]

Posted on July 03, 2017 at 13:26

Hi,

I use from stm32f103c8t6.

I haven't problem with i2c1 in this micro but at frequencies above 8mhz , i2c1 does not work.

While the i2c2 has no problems at all system frequencies.

I want use usb-cdc ,

for this reason I can not set the system frequency to 8mhz.

I set the system clock in the following ways , but i2c1 does not work!

What do you think the problem is?

pls help me if u can.

tnx!

[Tesla DeLorean]

Posted on July 03, 2017 at 16:37

>>

What do you think the problem is?

Perhaps an issue with the I2C1 settings or code?

>>

but i2c1 does not work!

Yes, so I don't know what that means. Take a look at the bus signals on a scope or analyzer, and confirm if those match the expectations of the attached devices. Check the address output, and ACK response from the device