Chip selection help

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#1
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I'm a happy camper with the atmega16, but realize I could use more resources, particularly another SPI. Do you have suggestions as to which part I should upgrade to?

I'm using all the IO, timers, UART and SPI in the atmega16. Code space has not yet hit the limit. For the future I would like to be able to boot an FPGA with the SPI, and for that I need more flash. I need a pretty large internal flash to hold the 2Mbits of FPGA code, so an external one would be good.

I may be able to use I2C on the atmega16, but I would prefer to use SPI for the external flash, as the I2C lines need to fill another role too. Also, there is a speed issue.

So which device is the best fit for atmega16 + one more SPI master?

Thanks,
Borge

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The ultimate 40 pin AVR is the mega1284P, more SRAM than any other AVR. It has "trade down" models in mega644p, mega324p, mega164p too. As well as SPI the USART can do SPI too (though not when it's being used as UART obviously!). You'll find the small model (164P) pretty close to the mega16 you are already using.

Another tack to take if you don't mind working with SMD are the big 64 and 100 pin chips like 640/1280/2560 and 1281/2561. Or how about looking at the Xmega range if you can work at 3.3V