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I2C communication with STM32F100

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hello

I am trying to communicate STM32F100C8T6B micro controller with MMA8653 Accelerometer using I2C
I sent the start condition and the adrress in correct way and I traced it using scope
the address is 0x3A but no ACK received from the Accelerometer.
this is the image of the Data and clock but no ACK

NewFile2.jpg

and also I tried to use I2C bit banging but the rising time and falling time of the port pin is 20 micro_second which exceed the max time in datasheet
and this is the waveform and how can I make the rise time and fall time max 300 nanosecond

NewFile3.jpg

thanks in advance
 
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how do you use i2c ? by pin toggling in software?

what is your clock frequency ? 20 microsecond pin rise time seems that you are using a very very slow clock frequency or a software emulation of i2c with delays maybe ??

according to

https://www.st.com/web/en/resource/technical/document/datasheet/CD00251732.pdf

page 63

2. fPCLK1 must be at least 2 MHz to achieve standard mode I2C frequencies. It must be at least 4 MHz to
achieve fast mode I2C frequencies. It must be a multiple of 10 MHz to reach the 400 kHz maximum I2C
fast mode clock.
 
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