The difference between FPGA and DSP (rough summary)

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The difference between FPGA and DSP (rough summary) [Copy link]

1. Structural features
FPGA
a. There are a large number of logic gates and triggers in the chip, most of which are lookup table structures, and the implementation process is mostly SRAM
b. It can be quickly designed and improved through hardware description language, and can be repeatedly programmed
c. The original logic configuration is generally lost after power failure; the timing is difficult to plan; it cannot handle multiple events; it is not suitable for conditional operations
DSP
a. It adopts the Harvard structure and improved Harvard structure with data and program separation, that is, the data bus and the address bus are separated, so that the program and data are stored in two separate spaces, allowing the instruction fetching and execution to overlap completely. That is to say, the next instruction can be fetched and decoded while the previous instruction is executed, which greatly improves the speed of the microprocessor.
b. DSP is programmed through assembly or high-level language (such as C language), and has a complete C language compiler
c. It has software and hardware waiting functions and can interface with various memories
d. It has interrupt processors and timing controllers, which are convenient for forming small-scale systems
e. It has DMA channel controllers and serial communication ports, etc., which are convenient for data transmission
f. It is suitable for mass production to reduce costs. The disadvantage is that once the (hardware) design is determined, it is not easy to modify
II. Internal resources
FPGA
a. FPGA focuses on designing hardware circuits with a certain function, and the internal resources are tiny units such as VersaTIles (ActelFPGA)
b. The wiring resources inside the FPGA connect the signals inside these functional modules and between modules to form a larger module.
c.FPGA can internally implement ALU, adder, multiplier, accumulator, FIFO, SRAM, DDRcontroller, FFT, HDLC, DMA, PWM and other digital circuits, which means that we need to use it to implement a specific or general hardware function one or more modules, and the details of these modules must be described in HDL to design and implement
d. It is commonly used to implement digital circuit modules, basically all digital circuits, traditional digital function modules, and digital processing modules with specific customer product requirements
e. IO drive capability or voltage are programmable
DSP
a. DSP is mainly algorithm processing, and internal resources are mainly multipliers, adders and other resources, with SPI interface, UART interface, and accept certain instruction sets
b. The internal resources are basically ready-made and need to be reconfigured according to customer needs
c. However, relatively speaking, its functions are limited, so it is mainly used in certain specific fields
d. There are many ready-made hardware modules, interfaces and controllers inside, but software programming settings are required to realize PWM control, interface control, UART interface, SPI interface and other functions
e. Due to the clock cycle limit of the instruction set, DSP cannot process too high signals
III. Applicable occasions
FPGA
FPAG is suitable for systems with high sampling rates (≥ several MHZ), high data rates, block diagram programming, fixed or repetitive processing tasks, and fixed point. ) Suitable for high-speed sampling frequencies, especially when tasks are relatively fixed or repetitive, as well as for prototypes and system development
DSP
DSP is suitable for systems with lower sampling rates, low data rates, multi-conditional operations, complex multi-algorithm tasks, C language programming, and systems using floating points. ) Suitable for multi-conditional processes at lower sampling rates, especially complex multi-algorithm tasks