Cisco Systems manual Cisco 4000 and Cisco 4000-M, Cisco 4000 Series Installation Guide, H3537

Memory Systems

when Flash memory does not contain a valid system image. In the Cisco 4500-M and 4700-M, the ROM monitor allows you to boot a system image from Flash memory if a boot helper image is not present in boot Flash memory.

The differences between the memory systems in the Cisco 4000 series allows enhanced software upgradability in the Cisco 4500-M and Cisco 4700-M.

Note See the appendixes “Cisco 4000 Series Virtual Configuration Register,”

“Cisco 4000-M ROM Monitor,” and “Cisco 4500-M and Cisco 4700-M ROM Monitor” for more information on the ROM Monitor.

Figure 1-2 Cisco 4000 Series Memory Systems and Software Images

Cisco 4000 and Cisco 4000-M

EPROM-based	Flash-memory based
Boot helper
(xboot)		Cisco IOS
ROM monitor

Cisco 4500, Cisco 4500-M, Cisco 4700, and Cisco 4700-M

EPROM-based	Flash-memory based
ROM monitor	Boot helper	Cisco IOS
	(xboot)		H3537

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