PM3350-SW View Datasheet(PDF) - PMC-Sierra
Part Name
Description
MFG CO.
'PM3350-SW' PDF : 224 Pages View PDF
ELAN 8X10
DATA SHEET
PMC-970109
ISSUE 3
PM3350 ELAN 8 X10
8 PORT ETHERNET SWITCH
System Memory Map
The ELAN 8x10 device uses a single linear (flat) byte-addressable 16 MB address
space for accessing memory and memory-mapped devices. The external memory map
for the system described above is quite straightforward. From the point of view of the
local memory bus, it is as follows (note that the memory addresses shown increase
upwards):
0xffffff
0xc00000
0xbfffff
0x800004
0x800000
0x4fffff
0x420000
0x41ffff
0x400000
0x3fffff
0x100000
0x0fffff
0x000000
Unused
Unused
LED Register
Unused
Boot EPROM
(32 kB; occupies 128 kB)
Unused
System DRAM
(1 MB)
Bank 3
Bank 2
Bank 1
Bank 0
Note that the 32 kB boot EPROM actually occupies 128 kB of address space. This is
because the EPROM is only 8 bits wide (i.e., a 32k x 8-bit configuration), and so is
connected to the least significant byte lane of the memory data bus. Hence each byte of
the EPROM takes up a full 32 bits worth of address space, leading to the 128 kB
requirement.
In a similar manner to the 8-bit wide EPROM, the LED register is mapped to the least
significant 8 bits of the data bus, but takes up a full 32 bits of address space. No other
device is shown as being mapped to the ELAN 8x10 address space in this simple and
minimal system; however, other devices (such as RS232-C serial ports) may be
interfaced as well, provided that firmware is developed to support them.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND PMC-SIERRA, INC. CUSTOMERS ONLY
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