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SC140 DSP Core Reference Manual
Introduction
1.3.1 Typical System-On-Chip Configuration
The SC140 is a high-performance general-purpose fixed-point DSP core, allowing it to support many
system-on-chip (SOC) configurations. A library of modules containing memories, peripherals,
accelerators, and other processor cores makes it possible for a variety of highly integrated and
cost-effective SOC devices to be built around the SC140. Figure 1-1 shows a block diagram of a typical
SOC chip made up of the SC140 core and associated SOC components (described below). Although not
indicated in this configuration, a typical SOC can contain more than one SC140 core.
In addition, an on-chip instruction set extension accelerator can be used to provide unique application
solutions such as graphics acceleration and video processing, which require specific arithmetic operations
in addition to the main instruction set.
Level 1 (L1) Memory Expansion Area
— On-chip L1 memories operating at full core frequency
are connected to the DSP core through this area. Memory is unified and can be used for both
program and data storage. Different technologies such as SRAM or ROM can be used to implement
the memory.
SC140 DSP core
— The processor in which the DSP application code is executed,
and which includes:
— The program sequencer unit (PSEQ)
— A data arithmetic logic unit (DALU) that contains four arithmetic logic units (ALU)
— An address generation unit (AGU) that contains two address arithmetic units (AAU)
Peripheral and Accelerator Expansion Area
— This area includes the functional units that
interface between the core and the application, most importantly the functions that send and receive
data from external input/output sources. In addition, this area includes accelerators that execute
portions of the application, in order to boost performance and decrease power consumption. This
area is application-specific and may or may not include various functional units such as:
— Host interface
— Synchronous serial interface
— Serial communication interface
— Viterbi accelerator
— Timers
— Filter coprocessors
System Expansion Area
— This area includes the functional units that interface between the DSP
core and the application (with the exception of the input/output peripherals and accelerators). This
area is application-specific, and may include various functional units such as:
— External memory interface
— Direct memory access (DMA) controller
— Cache controller for either data or program
— Interrupt control unit
— On-chip Level 2 (L2) memory expansion modules (see note below)
— Other processor cores
Note:
Level 2 memory expansion does not operate at full core frequency. The maximum operating
frequency of L2 memory depends on the memory technology. For example, embedded FLASH or
DRAM may operate at lower frequency than SRAM.