CPU vs DSP vs FPGA | Difference between CPU,DSP,FPGA

This page compares CPU vs DSP vs FPGA and describes difference between CPU,DSP and FPGA.

The figure-1 depicts 8085 CPU architecture.
Refer CPU Architecture➤.

The figure-2 depicts DSP architecture.
Refer DSP Architecture➤.

The figure-3 depicts FPGA Architecture.
Refer FPGA Architecture➤.

Following table-1 mentions difference between CPU and FPGA.

Specifications	CPU	FPGA
Computation	Fixed arithmetic engines	User configurable logic
I/O	Fixed and dedicated I/O ports	User configurable I/O ports
Programmability	Program execution	Registers will determine modes and also defines operating parameters.
Ease of programming	C simplifies development tasks, not required to be worried about hardware.	HDL requires knowledge of hardware
Upgrades and maintenance	less difficult	more difficult
Execution	Sequential	parallel
Throughput	lower	higher
Complex algorithm implementation	Easy	Difficult
Peripherals	Equipped with peripherals with RS232, USB, Ethernet etc.	Significant HW and SW effort is needed to implement these on FPGA chip.
Appropriate tasks	• decision making • complex analysis • lower data rate computation • block oriented tasks	• compute intensive algorithms • massively paralle operations • high data rate computation • streaming tasks

Following table-2 mentions difference between DSP and FPGA.

Specifications	DSP	FPGA
Application as per sample rate	Standalone DSP chips provide cost effective solution at few KHz of sample rate.	FPGA is best suitable for sample rates are in few MHz.
Data rate	For low data rates extra cycles are available and hence DSP is not bandwidth limited.	FPGA is easier and efficient to implement when I/O rates are greater than few Mbytes/sec.
Data width/precision	No limitation if data width is same as bus width of processor. Moreover there is no room for bit growth in the DSP algorithms.	Suitable for high precision/high data width as it has uniform parallel structure.
Implementation of decision trees or conditional branches.	DSPs are ideal.	FPGAs are not suitable. These tasks can be done with the use of embedded cores or microBlaze.

Refer our Page on what a microcontroller does.
Refer our Page on microcontroller programming using C language including example.
Refer our Page on microcontroller development kit manufacturers.
RS232 interface RS485 interface RS422 interface CAN interface SPI interface interface types and converters DigRF interface