A portion of the Flash has been allocated for use with the Journaling Flash File System (JFFS). The JFFS is mounted under the ‘/usr/’ directory in the standard µClinux distribution. For more information on the JFFS consult Appendix B. The rest of the Flash contains the read-only file system.

10000000

Linux Kernel

Read-Only File

System

JFFS

Figure 4. Layout of the Flash and Flash Schematic Layout of the Flash

Flash memory stores the following system components:

The Linux kernel, located at the beginning of flash.

The root file system as a read-only file system situated immediately after the kernel.

The Journaling Flash File System, which starts on the first sector boundary after the root file system.

No special consideration is given to the Flash boot sectors, since there is no monitor or special bootstrap. At reset, Flash memory is located at address 0x00000000 and is mirrored throughout the memory since it is controlled by chip select CSA0. At bootup, the kernel, being at the beginning of flash, is run immediately. One of the first actions of the kernel is to define the flash

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AMC 68VZ328 software manual Layout of the Flash and Flash Schematic Layout of the Flash