High Speed AVR

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#1
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All,

Just a heads up to let you know what I stumbled upon when browsing the Atmel www site recently.

There have been questions in the forum in the past about projects that require a lot of computation or over clocking (i can't remember specifics at the moment) but anyway I discovered this tucke away in the Wireless LAN section.

AT76C713
http://www.atmel.com/dyn/product...

It's basically an AVR with upto 48MHz CPU clock, with USB (12Mbits USB2.0) and External memory up to 32K plus the usual stuff. I've not heard it mentioned here so thought I'd let you guys know.

Tim

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Really interesting! Thanks!
So, were do I get one? findchips.com next...

Did you notice that it can execute code from SRAM. That could open the door to a new way of AVR programming.

/Alex

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This is not a stanadrd AVR.

Program execution is from on system SRAM and a boot ROM (programable once) downloads the program from an SPI device (dafalsh, EEPROM).

The AVR processor does not operate at 48Mhz but operates at 12Mhz but gernerates a 48Mhz clockfor the USB device. The program runs from a dedicated 16K internal SRAM with an second 8Kbyte internal SRAM for data. Thsi can be complemented with an external 32K byte SRAM used for data or program but then, like Mega128, you loose 19 I/O pins by doing this.

Note that the UARTS are PC standard and not AVR stardard which may mean their operation is differnt.

Lahlan

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I think you may have read the data sheet incorrectly. The external clock is run at 12MHz, but it appears there is a PLL which boosts this to a selectable rate between 16 and 48MHz.

And as for the UART being slightly different, if it is, what does it matter? It will still talk to another UART!

It's nice to see something a little different. And fast. :twisted:

Sacha.

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The bottleneck in the AVR's is it's program/data memories.

I believe you will find out the entire memory array is running from SRAM as it does inside the FPSLIC. This would explain why they can run it at 48 mhz if my assumption is correct (I have not seen the DS).

Regards

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the memory is all SRAM there is no flash. some if the internal data SRAM and all of the external SRAM can be used for program.