IBM manual Why NAND Flash, How to Program NAND Flash, MaxLoader User’s Guide

MaxLoader User’s Guide

Why NAND Flash

NAND-based flash is a low-cost high-capacity memory technology commonly used in large data applications such as digital cameras, 3G cell phones, PDAs, etc. In addition to using this data storage capability, manufacturers have found it beneficial in many cases to program code into NAND flash devices.

Embedded and mobile systems are increasingly using NAND flash for storage because it has various advantages over other storage technologies. As always though, life is a compromise and those advantages come with some limitations that need to be addressed to provide a robust flash file system.

Hard disks are not a viable storage option for many embedded and handheld systems because they are too big, too fragile and use too much power

Major difference is that NAND is shipped with marked bad blocks on the device, while NOR chips are shipped defect free. Thus, one expects to encounter some failures in NAND and should design accordingly.

How to Program NAND Flash

Since all Nand Flash contains BAD Block, NAND Flash developer should know:

•What is the input parameter of ROM writer for supporting the pre- programming in NAND flash memory

•Master image file.

•The number of NAND flash memory blocks. Refer to NAND flash memory specification.

•The number of Reservoir blocks in NAND flash memory.(Refer to GBBM specification.)

GBBM (Global Bad Block Management) manages the bad blocks of the whole NAND flash memory.

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