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DS507PP1
Copyright 2001 Cirrus Logic (All Rights Reserved)
3
EP7309
High-Performance, Low-Power System on Chip
Processor Core - ARM720T
The EP7309 incorporates an ARM 32-bit RISC
microcontroller that controls a wide range of on-chip
peripherals. The processor utilizes a three-stage pipeline
consisting of fetch, decode and execute stages. Key
features include:
ARM (32-bit) and Thumb (16-bit compressed)
instruction sets
Enhanced MMU for Microsoft Windows CE and other
operating systems
8 KB of 4-way set-associative cache.
Translation Look Aside Buffers with 64 Translated
Entries
Power Management
The EP7309 is designed for ultra-low-power operation.
Its core operates at only 2.5 V, while its I/O has an
operation range of 2.5 V
–
3.3 V allowing the device to
achieve a performance level equivalent to 60 MIPS. The
device has three basic power states:
Operating
—
This state is the full performance
state. All the clocks and peripheral logic are
enabled.
Idle
—
This state is the same as the Operating
State, except the CPU clock is halted while
waiting for an event such as a key press.
Standby
—
This state is equivalent to the
computer being switched off (no display), and
the main oscillator shut down. An event such as
a key press can wake-up the processor.
MaverickKey
Unique ID
MaverickKey unique hardware programmed IDs are a
solution to the growing concern over secure web content
and commerce. With Internet security playing an
important role in the delivery of digital media such as
books or music, traditional software methods are quickly
becoming unreliable. The MaverickKey unique IDs
provide OEMs with a method of utilizing specific
hardware IDs such as those assigned for SDMI (Secure
Digital Music Initiative) or any other authentication
mechanism.
Both a specific 32-bit ID as well as a 128-bit random ID is
programmed into the EP7309 through the use of laser
probing technology. These IDs can then be used to match
secure copyrighted content with the ID of the target
device the EP7309 is powering, and then deliver the
copyrighted information over a secure connection. In
addition, secure transactions can benefit by also
matching device IDs to server IDs. MaverickKey IDs
provide a level of hardware security required for today
’
s
Internet appliances.
Memory Interfaces
The EP7309 is equiped with a ROM/SRAM/FLASH-
style interface that has programmable wait-state timings
and includes burst-mode capability, with six chip selects
decoding six 256 MB sections of addressable space. For
maximum flexibility, each bank can be specified to be 8-,
16-, or 32-bits wide. This allows the use of 8-bit-wide
boot ROM options to minimize overall system cost. The
on-chip boot ROM can be used in product manufacturing
to serially download system code into system FLASH
memory.
To
further
minimize
requirements and cost, the ARM Thumb instruction set is
supported, providing for the use of high-speed 32-bit
operations in 16-bit op-codes and yielding industry-
leading code density.
system
memory
Digital Audio Capability
The EP7309 uses its powerful 32-bit RISC processing
engine to implement audio decompression algorithms in
software. The nature of the on-board RISC processor, and
the availability of efficient C-compilers and other
software development tools, ensures that a wide range of
audio decompression algorithms can easily be ported to
and run on the EP7309
Pin Mnemonic
I/O
Pin Description
BATOK
I
Battery ok input
nEXTPWR
I
External power supply sense
input
nPWRFL
I
Power fail sense input
nBATCHG
I
Battery changed sense input
Table A. Power Management Pin Assignments
Pin Mnemonic
I/O
Pin Description
nCS[5:0]
O
Chip select out
A[27:0]
O
Address output
D[31:0]
I/O
Data I/O
nMOE
O
ROM expansion OP enable
nMWE
O
ROM expansion write enable
HALFWORD
O
Halfword access select
output
WORD
O
Word access select output
WRITE
O
Transfer direction
Table B. Static Memory Interface Pin Assignments