[BCM20736] I2C bus question when power up

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Anonymous
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Hi Sir,

I have a question about the I2C bus. I measure the waveform by scope.

Whatever EEPROM have code program or not, I can see the same red circle waveform.

I also do remove the EEPROM and I still can see the same signal.

What's this signal meant to be?

IMG_0701.JPG

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MichaelF_56
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boont,

I will send you fran contact information offline.

View solution in original post

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BoonT_56
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can't say for sure. can i get a local representative to talk to you?

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Anonymous
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Okay.

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where are you based? can i have your email?

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MichaelF_56
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boont,

I will send you fran contact information offline.

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Anonymous
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It's software reset.

Below is from the data sheet of AT24C02:

122.PNG

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Anonymous
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Hi Roger,

Software reset for what device? EEPROM?

Is it possible to silence it?

Thanks,

Fran

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Anonymous
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One more question. Can I send the same signal by the i2cm API?

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Anonymous
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What type of Wireless device are you using?  The BCM20736 chip or the BCM20736S Module.?  Either way it seems on power up the device will try to read in a program from EEPROM on the I2C interface.  It sounds like this is what you are seeing.  I would doubt that this can be turned off since that's basic to how the thing is supposed to operate.  Not clear is what you are trying to accomplish... adding a memory chip which has what on it?  Where is the program that you want executed?

Eric

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What you explained is correct ehoffman

At a high level, on reset the firmware checks NVRAM for a valid image, and if not found, it goes into programming mode.

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Anonymous
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There is still one question. How to send the Software Reset signal by the API?

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Anonymous
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I use the BCM20736, not sip module.

I have a i2c chip on the same i2c bus and it's re-sync signal is same as the software reset signal.

Is it very sure the waveform is EEPROM's software reset signal?

If it's true, we can't put this i2c chip with the same bus to EEPROM...

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