Storing data in external flash chip using xmega

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#1
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Hi,

I will start a new project using an XMega chip soon.
In this project I have to store a large amount of data.

For the moment we are using a µSD card, the size is good (2GB) but we need to used a chip directly solder on the PCB.

The other restriction is the XMega selected has no EBI.

Do you think it is possible to connect a flash chip like the MT29F8G08ABABAWP from micron?

Thanks,

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To download that datasheet I had to register with Micron then the actual download asked me to agree to an NDA so what one can say in open forum about that chip is limited but...

Be warned that raw Nand arrays:

a) have huge pages. They aren't TOO bad in that chip but you won't be dealing with just 512 sectors as with microSD.

b) have no intelligence when it comes to bad block avoidance and wear levelling. In SD this is all done by a micro in the card but for raw NAND it becomes your responsiblity to handle it. Because of the NDA I cannot quote the datasheet but see page 93.

Now while I was on the Micro site I notice that as well as serial NAND they also have serial NOR. NOR is a much nicer kind of memory to work with but costs more for the same capacity and the capacities don't reach those available for NAND. 512Mb (64MB) seems to be the largest available.

If you go with Nand then there are companies who sell software stacks to do the bad block and wear levelling. This may be more cost effective (and safer) than trying to implement the things yourself.

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If I may reactivate this.

In my project I also use an AVR without EBI. To be precise it is Xmega128D3 connected with SuperFlash memory SST25VF032B through SPI. I would like to store much data/pictures in that memory. The SST can't be programmed as it's already soldered to the board.
Qustion:
Is it possible to put the data into SST without using µC internal memory? Or is it only possible with EBI?

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For small memories you might be better off with Atmel Dataflash. It has on-chip buffers that make life easier for the micro.

I too am interested in replacing large (512MB+) SD cards with on-board flash memory, but there are not many easy options available.

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Actually the best option might be to use an SD card controller IC to do all the hard work. The GL424 and AU7662B look suitable.

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We're looking at the same think. Using SD-card with SPI today, but would like to move to a solution based on a chip-based solution. What did you guys end up with? We have looked at some eMMC modules, but I'm unsure if it's possible to get them to work with an Xmega.