Kinetis MicrocontrollersのトピックRe: I2C communication in Kinetis K70

I2C communication in Kinetis K70

vrindamenon — Tue, 12 Dec 2017 10:32:58 GMT

I am trying to establish an I2C communication between MK70FN1M0VMJ12 microcontroller of Cortex M4 architecture and slave device which is a pressure sensor. I am using Kinetis Design Studio 3.2.0 .I have used the component I2C_LDD and tried with the sample code given in help for the component

Sending/Receiving data in the MASTER mode, with interrupt service

But I am not able to get the SDA or SCL waveforms.

Re: I2C communication in Kinetis K70

Robin_Shen — Mon, 18 Dec 2017 07:58:58 GMT

Hi vrinda,

Would you please attach your project here, so that I can check it on TWR-K70F120M board.
Please notice:
The I2C bus system uses a serial data line (SDA) and a serial clock line (SCL) for data transfers.
All devices connected to it must have open drain or open collector outputs. A logic AND function is exercised on both lines with external pull-up resistors. The value of these resistors depends on the system.

Best Regards,

Robin

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Re: I2C communication in Kinetis K70

Robin_Shen — Tue, 19 Dec 2017 02:15:28 GMT

Not sure if you are test it on TWR-K70F120M board.

If so: [B50 B51] or [A7 A8] of J7A can be used to observe the waveform of I2C. (Please notice don't use B21 and A9 of J7A, R106 and R109 are not place by default.)

There are external pull-up resistors (R54 R55) on I2C0_SCL I2C0_SDA lines at J5 on TWR-K70F120M board.

According to your project, it seems that you are not using the Sending/Receiving data in the MASTER mode, with interrupt service . You have Disable the interrupt service in that project.

Best Regards,

Robin