I2C Eeprom free clocking

MdeJong — Thu, 29 Oct 2020 09:14:29 GMT

Hello all,

After getting the second I2C bus working on the MCF5251 (the port configuration was wrong).

I have a new problem:

For error handling with EEPROMs the appliction note says, to generate 9 start sequences followed by one stop sequence.

To generate this sequence I have tried following code:

Code:

        MBAR2_MBCR = MBCR_MTX | MBCR_IEN;            MBAR2_MBCR |=  MBCR_MSTA;                /* generate start */        for (loop = 0; loop < 8; loop++)        {            MBAR2_MBCR |=  MBCR_RSTA;            /* generate restart */        }                MBAR2_MBCR &= ~MBCR_MSTA;                /* generate stop */        MBAR2_MBCR = 0;        MBAR2_MBCR = MBAR2_MBCR | MBCR_IEN;

It works when I single step through it, but not when running real-time, what am I doing wrong.

Regands Mark,

Re: I2C Eeprom free clocking

admin — Thu, 26 Jun 2008 21:04:57 GMT

Generating a START condition takes time. You cannot reasonably expect to set the RSTA bit 9 times in a row in a quick succession and have 9 START conditions on the bus with proper timing. You must have some sort of delay between the consecutive START conditions.

ColdFire/68K Microcontrollers and ProcessorsのトピックRe: I2C Eeprom free clocking

I2C Eeprom free clocking

Re: I2C Eeprom free clocking