---
title: "Features of DSP chip"
subject: "Microprocessor"
chapter: 6
key: "semester_4/microprocessor:dsp-features"
source: https://www.bctengineer.com/q/semester_4/microprocessor/dsp-features
site: BCT Engineering
---

# Features of DSP chip

Microprocessor · Chapter 6: Advanced Topics

- Asked in: 2072 Magh, 4 marks; 2071 Magh, 2 marks (asked 2 times)
- Video: [Basics of Digital Signal Processor - Programmable Digital Signal Processors (PDSP) - DTSP](https://www.youtube.com/watch?v=eoWPP7LgMLE) — Padmasri Naban
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_4/microprocessor/dsp-features
- Whole chapter: https://www.bctengineer.com/md/semester_4/microprocessor/chapter-6

## Question

What are the features of digital signal processors (DSP chip)?

## Short answer

DSPs have a hardware multiplier-accumulator, Harvard architecture with separate buses, pipelined parallel units, circular and bit-reversed addressing, zero-overhead loops, fast on-chip memory, fixed/floating point arithmetic, fast interrupts, and low power. Examples: TMS320, ADSP.

## Answer

A digital signal processor (DSP) is a microprocessor specially designed for fast real-time processing of digital signals such as audio, speech, image and radar data. Its main features are:

1. **Hardware multiplier-accumulator (MAC):** performs a multiplication and addition in one clock cycle, which is the basic operation in filters and FFT.
2. **Harvard architecture:** separate program and data memories and buses, so an instruction and data can be fetched at the same time. Many DSPs have two or more data buses.
3. **Pipelining and parallel units:** an ALU, multiplier and address generator work in parallel.
4. **Special addressing modes:** circular buffer addressing (for filters) and bit-reversed addressing (for FFT).
5. **Zero-overhead looping:** hardware loop counters repeat a block without time lost for branch instructions.
6. **Fast on-chip memory:** on-chip RAM and ROM, and DMA, for quick data transfer.
7. **Fixed-point or floating-point arithmetic**, with saturation arithmetic to avoid overflow errors.
8. **Real-time operation:** fast interrupt response and I/O interfaces (serial ports, ADC/DAC).
9. **Low power consumption and low cost**, suitable for embedded systems.

Examples: TI TMS320 series, Analog Devices ADSP, Motorola 56000.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What is the purpose of the hardware MAC unit in a DSP?
   A. Multiply and add in one clock cycle, the basic operation of filters and FFT
   B. Fetch the next instruction
   C. Control I/O
   D. Store data in cache
   Answer: A. Filtering and FFT consist of repeated multiply-accumulate operations. (Key point: MAC)

2. Why do DSPs use Harvard architecture?
   A. One bus reduces cost for both
   B. Separate program and data memories and buses let instruction and data be fetched together
   C. It is needed for floating point
   D. It removes the need for pipelining
   Answer: B. Simultaneous fetches increase throughput. (Key point: Harvard architecture)

3. Which addressing modes are special to DSPs?
   A. Circular buffer (filters) and bit-reversed (FFT)
   B. Indirect and indexed only
   C. Immediate and direct only
   D. Stack and segment
   Answer: A. These suit common signal processing algorithms. (Key point: Special addressing)

## Related in other subjects

- [Features and characteristics of DSP](https://www.bctengineer.com/question.md?key=semester_6%2Fembedded_system%3Adsp-features) — Embedded System, chapter 2, asked 3×
- [Digital signal and Gray code](https://www.bctengineer.com/question.md?key=semester_3%2Fdigital_logic%3Adigital-signal-gray-code) — Digital Logic, chapter 1, asked 2×
- [Digital IC signal levels and Gray code](https://www.bctengineer.com/question.md?key=semester_3%2Fdigital_logic%3Aic-signal-levels-gray-code) — Digital Logic, chapter 1, asked 2×
- [Analog vs digital signal; convert A2.64H](https://www.bctengineer.com/question.md?key=semester_3%2Fdigital_logic%3Aanalog-digital-convert-a264h) — Digital Logic, chapter 1