A power point presentation on the topic “Embedded Processors” with a total of 15 slides.
Embedded Processors
Introduction
The system functionality is partitioned into Hardware, Software, and the Interface. Software part runs on programmable processors (embedded processors).
Hardware part runs on IP blocks or custom designed Hardware blocks.
What is an embedded processor?
A programmable processor ‘embedded’ into an embedded system (on a chip). An embedded processor can be a general-purpose processor, DSP, microcontroller, or a processor optimized to a specific application.
Programming self-contained computers : End-user, application developer, system integrator, and component manufacturer are all separated.
Programming embedded processors : Most software is provided by system integrator.
Types of Embedded Processor
- Computational microprocessors.
- Embedded general purpose microprocessors.
- Microcontrollers
- Domain-specific processors
Characteristic of Embedded Processor
Application-specific functionality – specialized for one or one class of applications.
Deadline constrained operation – system may have to perform its function(s) within specific time periods to achieve successful results .
Resource challenged – systems typically are configured with a modest set of resources to meet the performance objectives.
Power efficient : Many systems are battery-powered and must conserve power to maximize the usable life of the system.
Form factor : Many systems are light weight and low volume to be used as components in host systems .
Manufactural : Usually small and inexpensive to manufacture based on the size and low complexity of the hardware.
Architecture
Single-issue RISC architecture : ARM, SH3-DSP, Xtensa, ARCtangent
Superscalar architecture : MIPS, PowerPC
VLIW architecture : TMS320C6x, ADSP-TS0xx, Saturn, Jazz
ST100 and Carmel provide instruction sets that support all these architectural features in one processor.
ST100: 16, 32, 128-bit instruction formats Carmel: 24, 48, 144-bit instruction formats
Configurability
- Fixed processors
- Fixed processor cores with reconfigurable logic
- Fixed processor cores given as soft cores
- Configurable processors
Fixed processors
8051, ARM, MIPS, PowerPC, SH3-DSP, TMS320x, Saturn, Carmel, ST100
Hard cores with fixed layouts or soft cores with synthesizable HDL descriptions
Instruction sets are fixed and are not supposed to be configured for application specific optimization.
Coprocessors can accompany fixed processor cores to improve the overall system performance.
The coprocessors can be synthesized for specific applications as in HP PICO project.
Fixed processor cores with reconfigurable logic
Virtex II Pro (Xilinx), Excalibur (Altera), E5 and A7 (Triscend), QuickMIPS (Quicklogic), RCP (Chameleon), FPSLIC (Atmel).
RCP has an ARC configurable processor embedded in it, but it is a pre-configured one.
Fixed processor cores given as soft cores
- MicroBlaze (Xilinx)
- Need to be synthesized to be programmed on a reconfigurable logic.
- Limited configuration can be done on peripherals and bus interfaces, but the instruction set is fixed.
Configurable processors
Processors that can be configured according to the application .
Especially processors whose instruction set architectures can be configured according to the application are called ASIPs (Application Specific Instruction set Processors)
Xtensa, ARCtangent, and Jazz provide basic cores and instruction sets. They can be configured or extended for the target application.
NIOS (Altera) is a configurable processor that can be programmed on a reconfigurable logic. However, only five opcodes (256 for NIOS II) can be used for user customizable instructions.
LISATek (merged to CoWare) and Target Compiler Technologies do not provide basic cores but start from scratch.
From an architecture description in a specific ADL (Architecture Description Language: LISA, nML), they generate a compiler, a simulator, and a synthesizable HDL.
Examples of Embedded Processor
- 8051
- ARM
- ARM7TDMI
- ARM922T
- ARM1022E
- ARM11
- XScale