LPI2C Mode

[adrianwenger]

Hi,

the reference manual says on page 1383 that baudrates above 400 kbit/s are not supported on the LPI2C device.

But on page 1384 it says in Features: LPI2C supports e.g.1Mbit/s (Fast Mode +)...

Now what is right?

Regards,

Adrian

[adrianwenger]

Hi Daniel,

thanks for clarification.

[danielmartynek]

Hi,

As per Device feature summary (Table 2-1), only high-drive pins are able to support 1 Mbps.

PTA2 and PTA3 are not high-drive pins. See IO Signal Description Input Multiplexing sheet(s) attached

to the RM.

Regards,

Daniel

[adrianwenger]

Hi Daniel,

thank you for your reply.

After getting in touch with the IO Signal Description Input Multiplexing sheet i assume that,

if i use the PTB6 high-drive pin (LPI2C0_SDA) and the PTA3 (LPI2C0_SCL) i will be able to send with 1MBit/s to the i²C slave.

Is that correct?

Regards,

Adrian

[danielmartynek]

Hi Adrian,

The functionality at that rate is guaranteed (even with bus capacitance of 400pF) only using high-drive pins for both SDA, SCL.  If you use pins without high-drive capability, it might work in case the bus capacitance is not too high, but is not guaranteed.

Regards,

Daniel

[adrianwenger]

Hi Martin,

can i use any of the high-drive Pins for the LPI2C0_SCL to get the 1MBit/s garanteed?

Regards,

Adrian

[danielmartynek · Accepted solution]

Hi,

You can use only PTA3 and PTB7 for LPI2C_SCL and none of them are high-drive.  I have just checked SDK I2C driver for S32K144 and the baud rate can be set only up to 400kbps. So as per all the information I have so far, the S32K144 doesn’t support 1000kbps baud rate.

Regards,

Daniel