Poking around in various forums, there seems to be a little misinformation about flash floating around here. I have some background on flash and I hope I can help clear some of that up.
There is flash where writes and erases "cycle" the flash. I believe the flash in CF and SD (NAND) is cycled on a write . There is even some flash where a READ cycles the flash :crooked:
However, that is NOT the case on an Axim. :exc: The flash in the Axim is Intel NOR flash. Intel NOR can be written an infinite number of times. A WRITE does not "cycle" Intel flash, only an ERASE is a "cycle". Intel flash can do 10k to 100K erases before the chip slows down below acceptable erase or write times. Data is retained, the function just slows down too far to be acceptable. Should you worry about erases? No! The software that manages the flash does not need to erase for every write or data update in flash. It uses a technique to break the larger flash erase blocks into smaller more data sized virtual units. When a data unit is changed or updated, the code invalidates the original virtual data unit and writes the new data to another virtual unit, updates pointers and goes on. The old data is there until a "clean-up" or "reclaim" cycle is required and THAT is when an erase will occur. The code is pretty smart and limits the amount of erases as much as possible in order to maximize the lifetime of the flash. If you managed to constantly write to built-in storage 24/7, it would probably take YEARS to hit the life expectancy of the flash. With normal usage, it will take tens to hundreds of years even at the "heavy usage" end of that scale. Use the "built-in" storage?? Heck yeah, it is much safer for your data than the battery backed RAM!!
You can see more information here:
www.intel.com\go\flash
There is a "cycling utility" I found here:
http://www.intel.com/design/flash/swb/cycling.htm#psm
Use this if you are worried about "wearing out" your flash. The block size is 256KB and has around 88 blocks on the Axim I think.
As for read/write speeds- the Intel flash reads at memory speeds but writes at Intel NOR write speeds. It is slightly constraigned by the file driver layer of WCE, but reads are fast. RAM is a bit faster reading (and a LOT faster writing) but goes bye-bye if you lose power (!!) If you search around you will find that the "storage card" benchmarks shows 'Built-in Storage" writes at the slower end of most CF or SD cards (but NOT the slowest) and reads much faster (in general).
Hope this helps clear up some of the misinformation here.
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