CCS/EK-TM4C129EXL: I2C (master_slave)

B.M

Tool/software: Code Composer Studio

Hello everyone i am trying to send data from master module (I2C0) to slave module (I2C2) without loop-back when i run the code loop-back is still implementing

could anyone who is familiar with I2C help me

over 6 years ago

0 Charles Tsai over 6 years ago

TI__Guru**** 191886 points

Hi,

Can you first tell what is not working instead of having your helpers to go through the entire code? If you are connecting the I2C0 and I2C2 on the bus then you must have proper pullup resistor on SCL and SDA bus. Do you have that? Do you have either logic analyzer capture or the scope capture of the I2C bus?

0 B.M over 6 years ago in reply to Charles Tsai

Expert 1660 points

actually i didn't connect pullup resistors to SCL and SDA

What's the recommended value for them. did you track the code above is everything correct?

0 Charles Tsai over 6 years ago in reply to B.M

TI__Guru**** 191886 points

Hi,

You can start with 4.7k as a rule of thumb. If you want to be precise you can refer to this app note on pull resistor calculation.http://www.ti.com/lit/SLVA689. I think between 4.7k to 10k should be fine for most applications.

I think once you add the pullup, you can easily debug your code with the aid of the scope or LA. Glancing your code, I don't spot something wrong.

0 B.M over 6 years ago in reply to Charles Tsai

Expert 1660 points

Thanks the I2C works now

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CCS/EK-TM4C129EXL: I2C (master_slave)