BCM20737S's P1 How can I use it as gpio input in?

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Anonymous
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How can I use BCM20737S's P1 as gpio input in?
I tried to use it as input with 10kΩ pull up same as other gpio .

Does it have any special configuration?
Thank you.

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1 Solution
Anonymous
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P1 of BCM20737S is connected with WP of internal EEPROM.

So I recommend to use another pin.

View solution in original post

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6 Replies
Anonymous
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P1 of BCM20737S is connected with WP of internal EEPROM.

So I recommend to use another pin.

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Anonymous
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Thank you Sir.

But I'v already made PCB which use P1 as an input pin...

and datasheet says P1 default is input pin.

Then I must use P1 as input.

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Anonymous
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Thank you msf_mmfae.

I read this document and it says 25 is ”GPIO:P1” and "Default direction: input" then I decided to use P1 as GPIO in put with 10K pull-up. 

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Anonymous
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I had problems using the device with the pullup in place when using the 20737S. If I remember correctly using the NVRAM functions didn't work. I didn't chase down the issue since removing the pullup solved the problem. Do I have to set the P1 to low in addition to using bleprofile_WriteNVRAM()?

Regards,

Kilian

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As previously noted, physical pin 25/P1 is tied to the EEPROM WP pin internally, so the alternate functions listed in the current datasheet are not available within the module (only the SOC).  In addition, a 10K pull-up is recommended (not necessarily required) on this pin as well. 

Essentially, the manufacture of the module found that in some use cases that the 10K resistor was required externally to prevent errors during boot.  Because we could not pin point all the use cases where it would be required, we ask that customers provide the external pull-up as a preventative measure.

I am not aware of any software changes that need to be implemented in addition to the pull-up.