Forums - Using PIO2 as IO

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Using PIO2 as IO
ilans
Join Date: 14 Sep 16
Posts: 7
Posted: Wed, 2017-06-21 01:00

Hello, All!

According to the datasheet, PIO2 is used as an enable pin for the EEPROM, and as an IO.

I wanted to make sure, that, after the chip is booted and the application is running,  assuming we don't write or read EEPROM, can PIO2  be used freely as an IO?

1. connected to EERPOM and another device

2. connected only to another device (assuming we don't boot from eeprom)

Thanks!

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Acutetech
Join Date: 29 Jul 16
Posts: 25
Posted: Thu, 2017-06-29 03:36

Hi Ilans

You will probably need the EEPROM after booting - certainly if your application uses the NVM read/write functions. These are used by most of the CSR sample apps - for example to store bonding information.

You can programmatically control PIO2 while it is connected to the EEPROM as its power pin, but remember that your other device will see PIO2 going high whenever yor EEPROM is accessed. It might be appropriate to use PIO2 as the power supply or enable pin for other hardware, if you can accept that both the EEPROM and your other hardware will both be on or off together.

It is just possible that you might be able to disconnect PIO2 from the EEPROM and leave the EEPROM powered all the time, but (a) that would have implications for power consumption and (b) the chip is going to toggle PIO2 when it boots anyway. So not a good idea.

Regards - Charles

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Acutetech
Join Date: 29 Jul 16
Posts: 25
Posted: Thu, 2017-06-29 03:37

Hi Ilans

You will probably need the EEPROM after booting - certainly if your application uses the NVM read/write functions. These are used by most of the CSR sample apps - for example to store bonding information.

You can programmatically control PIO2 while it is connected to the EEPROM as its power pin, but remember that your other device will see PIO2 going high whenever yor EEPROM is accessed. It might be appropriate to use PIO2 as the power supply or enable pin for other hardware, if you can accept that both the EEPROM and your other hardware will both be on or off together.

It is just possible that you might be able to disconnect PIO2 from the EEPROM and leave the EEPROM powered all the time, but (a) that would have implications for power consumption and (b) the chip is going to toggle PIO2 when it boots anyway. So not a good idea.

Regards - Charles

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