A problem about the I2C Fast mode plus of STM32H750VBT6

[PKB404]

I configured SYSCLK to 480 MHz and set the I2C1 peripheral clock frequency to 120 MHz. For I2C1's timing settings, I selected Fast Mode Plus (1 MHz) and applied the timing register value 0x0050174F, the setting about maximum output speed of SDA and SCL are Very High.However, when observing the I2C1_SCL line with a logic analyzer, the actual output clock frequency is only 890 kHz.

[PKB404]

I tested this with 1 kΩ, 1.2 kΩ, and 2.2 kΩ pull-up resistors, but the SCL frequency remained unchanged at 890 kHz. Has anyone encountered this issue? Any insights would be appreciated.

[TDK]

I2C clock speed is not a guarantee. It has to wait for edges to happen, so the actual clock you get is not exact like it is with SPI. This is expected and unavoidable.