Figure 4: Cisco 1604 and 1604R Rear Panel
Figure 5: Cisco 1605R Rear Panel
The Cisco 1600 series routers are either run−from−Flash or run−from−RAM models. Router model names
with an R are run−from−RAM routers; all other models are run−from−Flash. A more detailed description
of these two memory architectures are described in Cisco 1600 Series Memory Architecture and Comparison
of Cisco 1601−Cisco 1604, and Cisco 1605−R.
Block Diagram
The following figure represents the basic block diagram of the 1600 router:
The basic characteristics and functions of each block in this platform can be summarized as:
Processor: The processor used in the 160x series is the Motorola 68360 Complex Instruction Set
Computer (CISC). The main job of the processor is to load instructions defined in Cisco IOS®
software from PCMCIA Flash or from RAM (for the R models) and execute them, which basically
involves some manipulation of data. The M68360 is an embedded controller, and has a 32−bit
address, a 32−bit data bus, a 33 MHz internal clock, and a built−in Serial Communication Channels
(SCC).
•
Memory: This is discussed in more detail in the Memory section below.•
Buses are used by the CPU for accessing various components of the system and transferring
instructions and data to or from specified memory addresses.
•
CPU Bus is for high speed operations, with direct processor access. It has a 32−bit address
and 32−bit data at 33 MHz. These include access to dynamic RAM (DRAM), Boot ROM,
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Cisco 1600 Series Router Architecture