Motorola DSP56012 사용자 설명서

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Overview
DSP56012 Architectural Overview
 
MOTOROLA
DSP56012 User’s Manual 
1-9
The DSP56000 core is dual-natured in that there are two independent data memory 
spaces, two address arithmetic units, and a Data ALU that has two accumulators and 
two shifter/limiters. The duality of the architecture makes it easier to write software 
for DSP applications. For example, data is naturally partitioned into coefficient and 
data spaces for filtering and transformations, and into real and imaginary spaces for 
performing complex arithmetic. 
Note:
Although the DSP56000 core has built-in support for external memory 
expansion, the DSP56012 does not implement this function. For DSP56012 
applications, external memory expansion is a function of the host processor.
The DSP56000 architecture is especially suited for audio applications since its 
arithmetic operations are executed on 24-bit or 48-bit data words. This is a significant 
advantage for audio over 16-bit and 32-bit architectures—16-bit DSP architectures 
have insufficient precision for CD-quality sound, and while 32-bit DSP architectures 
possess the necessary precision, with extra silicon and cost overhead they are not 
suitable for high-volume, cost-driven audio applications
Figure 1-1  DSP56012 Block Diagram
Y Data 
Memory
X Data 
Memory
Program 
Memory
Program Control Unit
24-Bit
DSP56000 
Core
OnCE
TM
 Port
PLL
Clock
Gen.
8
9
5
2
16-Bit Bus
24-Bit Bus
Data ALU
24 
×
 24 + 56 
 56-Bit MAC
Two 56-Bit Accumulators
Program
Interrupt 
Controller
Program 
Decode 
Controller
Program 
Address 
Generator
4
IRQA, IRQB, NMI, RESET
4
3
Internal 
Data
 Bus 
Switch
Address
Generation 
Unit
PAB
XAB
YAB
GDB
PDB
XDB
YDB
General 
Purpose 
I/O
(GPIO)
Digital 
Audio 
Transmitter 
(DAX)
Serial 
Audio 
Interface 
(SAI)
Serial 
Host 
Interface 
(SHI)
Parallel 
Host 
Interface 
(HI)
15
EXTAL
Expansion
Area