Artesyn COMX-P40x0 ENP2 Installation and Use (August 2014) - Manual (Page 60)

Functional Description
COMX-P40x0 ENP2 Installation and Use (6806800R95B) 60
4.5 Local Bus
The 16-bit wide local bus is connected to a 2 Gb or 256 MB NOR Flash and an 8 Gb or 1 GB NAND
FLASH. The NOR FLASH is used to store the RCW data (active and alternates), FMan microcode,
DTB, U-Boot, demo Linux kernel and associated basic ramdisk. By default, the NAND FLASH is
used to store an alternate Linux filesystem. The local bus is also extended to the COM Express
connectors. There are six chip select signals supported - CS0, CS1 and CS3-6. CS0 is reserved
for the boot device and defaults to the NOR FLASH. CS1 defaults to the NAND FLASH. CS0 and
CS1 can be swapped between the NOR and NAND FLASH by driving the COM Express
connector pin A30 high (+3.3V). CS3-6 are extended to the COM Express connector and are
available for use.
The following figure illustrates the distribution of local bus on the module:
Figure 4-2 Distribution of Local Bus on P40x0