LPC2148 Philips, LPC2148 Datasheet - Page 10

• Manufacturer Part Number: LPC2148
• Description: 16/32 Bit Microcontroller
• Manufacturer: Philips

Philips Semiconductors
6. Functional description
9397 750 14985
Preliminary data sheet
6.1 Architectural overview
6.2 On-chip flash program memory
6.3 On-chip static RAM
The ARM7TDMI-S is a general purpose 32-bit microprocessor, which offers high
performance and very low power consumption. The ARM architecture is based on
Reduced Instruction Set Computer (RISC) principles, and the instruction set and related
decode mechanism are much simpler than those of microprogrammed Complex
Instruction Set Computers. This simplicity results in a high instruction throughput and
impressive real-time interrupt response from a small and cost-effective processor core.
Pipeline techniques are employed so that all parts of the processing and memory systems
can operate continuously. Typically, while one instruction is being executed, its successor
is being decoded, and a third instruction is being fetched from memory.
The ARM7TDMI-S processor also employs a unique architectural strategy known as
Thumb, which makes it ideally suited to high-volume applications with memory
restrictions, or applications where code density is an issue.
The key idea behind Thumb is that of a super-reduced instruction set. Essentially, the
ARM7TDMI-S processor has two instruction sets:
The Thumb set’s 16-bit instruction length allows it to approach twice the density of
standard ARM code while retaining most of the ARM’s performance advantage over a
traditional 16-bit processor using 16-bit registers. This is possible because Thumb code
operates on the same 32-bit register set as ARM code.
Thumb code is able to provide up to 65 % of the code size of ARM, and 160 % of the
performance of an equivalent ARM processor connected to a 16-bit memory system.
The LPC2142/2148 incorporate a 64 kB and 512 kB flash memory system respectively.
This memory may be used for both code and data storage. Programming of the flash
memory may be accomplished in several ways. It may be programmed In System via the
serial port. The application program may also erase and/or program the flash while the
application is running, allowing a great degree of flexibility for data storage field firmware
upgrades, etc. Due to the architectural solution chosen for an on-chip bootloader, flash
memory available for user’s code on LPC2142/2148 is 64 and 500 kB respectively.
The LPC2142/2148 flash memory provides a minimum of 100,000 erase/write cycles and
20 years of data-retention.
On-chip static RAM may be used for code and/or data storage. The SRAM may be
accessed as 8-bits, 16-bits, and 32-bits. The LPC2142/2148 provide 16 kB and 32 kB of
static RAM.
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The standard 32-bit ARM set.
A 16-bit Thumb set.
Rev. 01 — 22 June 2005
Single-chip 16/32-bit microcontrollers
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
LPC2142/2148
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