Does ncs 2.5.0 implement the workaround for TWIM timing spec anomaly 219?

[tellg]

Does ncs 2.5.0 implement the suggested workaround for https://docs.nordicsemi.com/bundle/errata_nRF52840_Rev3/page/ERR/nRF52840/Rev3/latest/anomaly_840_219.html ?

If not, will it be implemeted later?

[tellg]

So far so good, but will test the external sensor a bit more before concluding.

[Håkon Alseth]

Sounds good. Let me know if anything out of the ordinary happens.

 

Kind regards,

Håkon

[tellg]

For ncs, I managed to fix it like this, so that this code runs before main but after driver init:

static int fix_i2c_anomaly(void)
{
    const struct device *i2c_dev = DEVICE_DT_GET(DT_NODELABEL(i2c0));

    if (i2c_dev) 
    {
        NRF_TWIM_Type *twim = NRF_TWIM0; // Use TWIM instance 0

        if (twim->FREQUENCY == NRF_TWIM_FREQ_400K)
        {
            // Set the I2C frequency to 370 kHz
            // https://docs.nordicsemi.com/bundle/errata_nRF52840_Rev3/page/ERR/nRF52840/Rev3/latest/anomaly_840_219.html
            twim->FREQUENCY = 0x05EB8000UL;
        }
    }

    return 0;
}

SYS_INIT(fix_i2c_anomaly, APPLICATION, 0);

 

[Håkon Alseth]

Hi,

 

Thanks for updating.

Your code is good for specifically i2c0, but if you use other instances, you also need to remember to update the "twim" pointer.

One option can be to do something like in the driver:

https://github.com/nrfconnect/sdk-zephyr/blob/v3.4.99-ncs1-1/drivers/i2c/i2c_nrfx_twim.c#L226

 

Then you can access the register similar to this:

https://github.com/nrfconnect/sdk-zephyr/blob/v3.4.99-ncs1-1/drivers/i2c/i2c_nrfx_twim.c#L234

 

Not strictly needed to this scenario, but just something to consider if you're using other i2c instances.

 

Kind regards,

Håkon

[tellg]

Thank you

My only comment is that one cannot use nrf_twim_frequency_set as it only accepts enums of type nrf_twim_frequency_t