
26
Agere Systems Inc.
T8302 Internet Protocol Telephone
Advanced RISC Machine (
ARM
)
Data Sheet
July 2001
3 Overview
The IPT_
ARM
contains several system-level functions that would typically require separate ICs. The following func-
tions are implemented on a single IC: a full 32-bit microprocessor with integrated cache, a complete two-port Ether-
net subsystem including a two-port repeater, a host USB, IrDA, UART, and SSI communications controllers. In
addition, there are general peripheral controllers including parallel I/O, key scanning, and LED control circuitry.
The IPT_
ARM
processor communicates with memory through the
AMBA
* ASB bus. This bus supports 32-bit word
accesses as well as half-word and byte accesses. The
AMBA
APB bridge provides a flexible interface for communi-
cating with the on-chip peripheral devices. The IPT_
ARM
can be used in a system that meets European Class B
emissions requirements.
The IPT_
ARM
block diagram in
Figure 2 on page 27
shows the following system blocks:
I
ARM
940T 32-bit CPU.
I
AMBA
ASB bus for high-performance memory access.
I
AMBA
APB bridge for communication with and control of IPT_
ARM
peripherals.
I
Four-channel DMA controller to move data from memory to memory or to/from memory from/to IPT_
ARM
peripherals.
I
Interrupt controller with programmable priority for efficient system operation.
I
Reset/clock management controller with internal PLL circuitry to provide programmable clock frequencies,
including a one-second real time clock.
I
General timer unit with four interval timers and a watchdog timer.
I
External memory interface with support for SDRAM, FLASH, and SRAM memories.
I
DSP communications controller with interrupts, token registers, and buffer memories for efficient interprocessor
communications.
I
1K x 32 internal SRAM for general-purpose storage.
I
Ethernet MAC.
I
Two-port Ethernet repeater.
I
Two Ethernet PHYs.
I
USB host controller.
I
IrDA communications controller.
I
UART communications controller.
I
SSI communications controller.
I
16-bit parallel port interface.
I
Key and lamp controller (KLC).
I
JTAG.
*
AMBA
is a trademark of
ARM
Limited.