CN202535321U - Dual-tone multi-frequency signal generator based on FPGA - Google Patents

Abstract

The utility model relates to a dual-tone multifrequency signal generator based on FPGA, including adder and two signal processing modules, adder and two signal processing modules realize on a slice FPGA, each signal processing module respectively including cascaded frequency control register, phase accumulator in proper order, be used for storing waveform data's ROM and output module, two output module's output all is connected to the adder. The utility model discloses a dual-tone multifrequency generator's based on FPGA digital logic only realizes in a slice FPGA, has reduced the area of circuit board, has improved the reliability of integrated circuit board, has reduced the fault rate. The method has the characteristics of low cost, high integration level, easiness in debugging, good reliability and good portability.

Description

A kind of dual tone multi-frequency signal generator based on FPGA

Technical field

The utility model relates to electronic communication field, relates in particular to a kind of dual tone multi-frequency signal generator based on FPGA.

Background technology

In traditional dual tone multi-frequency signal generator, mainly be compositions such as discrete device and small scale integrated circuit, and accomplish corresponding logic function at present with this.The required logic circuit device of such circuit structure is generally more, and the integrated circuit volume is bigger; Because device is numerous, therefore the reliability of device also decreases.When system need increase new function, often need design again circuit, increased the cycle and the expense of design widely.

The utility model content

But the purpose of the utility model provides a kind of stable performance, be easy to debug smooth upgrade, flexibility and the portable good dual tone multi-frequency signal generator based on FPGA.

For achieving the above object, the utility model adopts following technical scheme:

A kind of dual tone multi-frequency signal generator based on FPGA; Comprise adder and two signal processing modules; It is characterized in that: said adder and two signal processing modules are realized on a slice FPGA; Each said signal processing module comprise respectively cascade successively FREQUENCY CONTROL register, phase accumulator, be used for the ROM and the output module of stored waveform data, the output of two said output modules all is connected to adder.

The utility model and prior art relatively have following advantage:

1. the Digital Logic based on the dtmf generator of FPGA of the utility model only realizes in a slice FPGA, and conventional method will use 4-5 sheet chip to come the common logic function of accomplishing the utility model.The utility model has reduced the area of circuit board, has improved the reliability of integrated circuit board, has reduced failure rate.It is low to have cost, and integrated level is high, is easy to debugging, the characteristics of good reliability.

2. transplantability is good, but smooth upgrade.When the stronger function of needs increase, needn't revise the external hardware circuit, utilize the characteristic of FPGA reconfigurable system; Can increase new function for system easily; Realize more complex processing, can realize smooth upgrade, improved the flexibility and the portability of design of Controller greatly.

Description of drawings

Fig. 1 is the inside major function structured flowchart based on the dual tone multi-frequency signal generator of FPGA of the utility model

Fig. 2 is the application system block diagram based on the dual tone multi-frequency signal generator of FPGA of the utility model

Embodiment

Referring to Fig. 1; Dual tone multi-frequency signal generator based on FPGA; Comprise adder and two signal processing modules; Said adder and two signal processing modules realize on a slice FPGA, each said signal processing module comprise respectively cascade successively FREQUENCY CONTROL register, phase accumulator, be used for the ROM and the output module of stored waveform data, the output of two said output modules all is connected to adder.Phase accumulator is at each reference clock source f _cClock pulse when input, accomplish frequency control word and add up once, the data of the output of phase accumulator are exactly the phase place of composite signal, simultaneously the signal frequency of overflowing frequency DDS output just of phase accumulator.Referring to Fig. 2, the host computer that passes through of dual tone multi-frequency signal generator produces telephone number signal, through serial communication; Send on the single-chip microcomputer, table look-up after single-chip microcomputer is received, produce pairing two frequency control words; P2, P0 mouth through single-chip microcomputer are latched in the internal register of FPGA under the edge pulse of P3.1 and P3.2 mouth respectively, and FPGA obtains two-way frequency number horizontal or vertical scroll of calligraphy value signal according to the frequency control word that obtains; Through adder, deliver to D/A, obtain corresponding touch-tone signal.The parameterization macro module ROM that carries in the EP1C6 chip in the Cyclone series of FPGA employing altera corp stores waveform, and this device has characteristics such as low-power consumption, high-performance and low cost.

Claims (1)

1. dual tone multi-frequency signal generator based on FPGA; Comprise adder and two signal processing modules; It is characterized in that: said adder and two signal processing modules are realized on a slice FPGA; Each said signal processing module comprise respectively cascade successively FREQUENCY CONTROL register, phase accumulator, be used for the ROM and the output module of stored waveform data, the output of two said output modules all is connected to adder.

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