What is the maximum SPI clock speed in SAM E70?

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Hi guys, got any idea like what will be the maximum SPI clock speed in Atmel SAM E70?

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Silly beans are always silly
:)

Last Edited: Wed. Feb 8, 2017 - 12:02 PM
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in page 931, section 40.7.3.3 Clock Generation

It says that the SPI clock is generated by dividing peripheral clock between value 1 and 255.

If that is so, then if my peripheral clock is 300MHz, then the SPI clock can vary between 300MHz to 1.17MHz.

 

Am I right?

 

Silly beans are always silly
:)

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The maximum peripheral clock is 150 MHz.

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i think it should be something like this:

 

Atmel-11296D-ATARM-SAM E70-Datasheet_19-Jan-16

 

56.14.1.5 SPI Characteristics

Master Write Mode

maximum pad speed (see Section 56.13.1.3 “I/O Characteristics”)

 

Package 144pin

SPI0_SPCK - PD22 - GPIO_AD

SPI1_SPCK - PC24 - GPIO_AD

 

Pin Group 3 = GPIO_AD

Pin Group3(3) Maximum output frequency

Drive Level High: 75MHz

Drive Level Low: 50MHz

 

 

Master Read Mode

For a non-volatile memory with tvalid (or tv) = 5 ns, fSPCKmax = 63 MHz at VDDIO = 3.3V.

 

 

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My bad.

So, yes, with 300MHz core clock, the peripheral clock can have a max of 150MHz.

You are right.

Silly beans are always silly
:)

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Now am feeling pretty confused.

Silly beans are always silly
:)

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Why?

 

Max. CoreClock with 300MHz is fine

From there you get max. Peripheral Clock 150MHz

The internal SPI part can operate with peripheral clock

 

so far so good. but that does not mean you necessarily get that frequenzy out onto the actual pin.

You still have to consider the (see datasheet) 56. Electrical Characteristics -> 56.14 Timings for STH Conditions -> 56.14.1.5 SPI Characteristics

as well as 56.13 Timings for Worst-Case Conditions -> 56.13.1.5 SPI Characteristics

in there you get equatios to consider.

 

And as a rough estimate: you got the 56.13.1.13 IO Characteristics -> in there you have max. freq. for pin_group types. when looking at the SPI pin e.g. SPI0_SPCK which is on 144pin package at PD22 which is in pin_group GPIO_AD you get what i wrote

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yep,

its pretty clear,

E70tryhard seems like a good title.

Thanks a lot.

 

Again, if you have any experience in USB or external flash, then you can help me.

I got stuck on few things.

Silly beans are always silly
:)