Core Architecture Features

SoC

DSP expansion area

Standard I/O Peripherals

Application specific accelerators

General purpose programmable accelerators

System expansion area

External memory interface

PLL

Level-2 caches

DMA

On-chip RAM and ROM

 

Host interface

 

Other micro-controllers

 

SC140 platform

 

 

 

Trace

 

PIC

buffer

 

 

 

 

 

 

 

Bus switch & interfaces

Instruction

Data

cache

cache

Unified M1

prog. & data

memory

RAM ROM

JTAG

EOnCE

ISAP

 

 

 

 

 

 

 

 

SC140 core

 

 

P

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

XA

 

 

 

 

 

 

XB

Figure 1-1. Block Diagram of a Typical SoC Configuration with the SC140 Core

1.3.2 Variable Length Execution Set (VLES) Software Model

The VLES software model is the instruction grouping used by the SC140 to address the requirements of DSP kernels. Using an orthogonal compiler-friendly instruction set, this model maintains a compact code density for applications.

All SC140 instruction words are 16 bits wide. Most instructions are encoded with one word. Each SC140 instruction encodes an atomic (lowest-level) operation. For example, MAC and store (move) instructions are encoded in 16 bits. Since atomic operations need fewer bits to encode, the 16-bit instruction set becomes fully orthogonal and very rich in the functionality it supports.

In order to execute signal processing kernels, a set of SC140 instructions can be grouped to be executed in parallel. The PSEQ performs this automatically with up to four DALU instructions and two AGU instructions executed at the same time.

SC140 DSP Core Reference Manual

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Freescale Semiconductor Variable Length Execution Set Vles Software Model, SoC DSP expansion area, SC140 platform