What is meant by I/O Type GPIO_AD?

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In SAM E70 datasheet, i can see that the I/O Type are marked as CLOCK, GPIO, GPIO_CLK, GPIO_AD, GPIO_MLB.

what are the differences between these?

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Silly beans are always silly
:)

Last Edited: Mon. Apr 3, 2017 - 03:27 PM
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Specifications differ somewhat, but I think this is pretty close.

GPIO_AD  General Purpose InputOutput _ Analog Device   in short the port pin can work as a Analog signal input!

Hope this helps.

/Bosse

 

Technicians PASCAL developer

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Looking at the datasheet, it seems to be a label as to which "pin group" the pin is in, which in turn is probably related to which pin is "closest" WRT powering that section of the chip, and various "per pin group" power limits.  (It could certainly use some better explanation!)

 

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I/O pins are classified into different groups (CLOCK, GPIO, GPIO_CLK etc) based on the functionality/characteristics they are associated with.

• GPIO : Generic GPIO pin
• CLOCK: Exclusive clock pin
• GPIO_CLK: Faster signals (could be used as clock pins for peripherals)
• GPIO_AD: (Analog/Digital pin)
• GPIO_MLB: Used for Media LB. SAMV71 device has MediaLB module.

This is what atmel says.

So, GPIO_AD is in fact analog/digital pin(s).

But AFEC handles all the analog to digital conversions, that means these pins can't be used for ADC operation.

So I am wondering what is meant by analog/digital pin?

Silly beans are always silly
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Harikrishnan911 wrote:
So I am wondering what is meant by analog/digital pin?

A pin which supports both analogue and digital functions - as opposed to the others, which are purely digital only.

 

 

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could you give me an example of the kind of analog functions supported by the pin?
 

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Harikrishnan911 wrote:
could you give me an example of the kind of analog functions supported by the pin?

ADC - Analog to digital converter. - AKA analogRead()

 

"When all else fails, read the directions"

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Harikrishnan911 wrote:
could you give me an example of the kind of analog functions supported by the pin?

Surely, you can see that in the datasheet?

 

For those pins marked as "GPIO_AD", look at what analogue function(s) get multiplexed to them!

 

 

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Sadly, all GPIO_AD pins hasn't got analog functionality. Only a fraction of these pin can be used for analog application. (All the analog pins can be found in SAM E70 Datasheet Table 50-2) Rest of the pins are purely digital.

The only reason to justify their GPIO_AD type is their electrical characteristics. Strange but true. I wonder why couldn't they name these digital pins as GPIO* or something different rather that GPIO_AD, which can easily deceive any designer.

 

So, don't get fooled by the type GPIO_AD. Always double check with the AFEC multiplexed pins and make no mistakes like what we just did.

sad

Silly beans are always silly
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