mc68hc916y3 Freescale Semiconductor, Inc, mc68hc916y3 Datasheet - Page 108

• Manufacturer Part Number: mc68hc916y3
• Description: Mc68hc16y3 16 Bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

4.16 Digital Signal Processing
4-46
MOTOROLA
The CPU16 performs low-frequency digital signal processing (DSP) algorithms in real
time. The most common DSP operation in embedded control applications is filtering,
but the CPU16 can perform several other useful DSP functions. These include auto-
correlation (detecting a periodic signal in the presence of noise), cross-correlation
(determining the presence of a defined periodic signal), and closed-loop control
routines (selective filtration in a feedback path).
Although derivation of DSP algorithms is often a complex mathematical task, the
algorithms themselves typically consist of a series of multiply and accumulate (MAC)
operations. The CPU16 contains a dedicated set of registers that perform MAC
operations. As a group, these registers are called the MAC unit.
DSP operations generally require a large number of MAC iterations. The CPU16
instruction set includes instructions that perform MAC setup and repetitive MAC
operations. Other instructions, such as 32-bit load and store instructions, can also be
used in DSP routines.
Many DSP algorithms require extensive data address manipulation. To increase
throughput, the CPU16 performs effective address calculations and data prefetches
during MAC operations. In addition, the MAC unit provides modulo addressing to
implement circular DSP buffers efficiently.
Refer to the CPU16 Reference Manual (CPU16RM/AD) for detailed information con-
cerning the MAC unit and execution of DSP instructions.
Freescale Semiconductor, Inc.
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MC68HC16Y3/916Y3
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