USB接口信號發(fā)生器,usb,接口,信號發(fā)生器 摘 要 本系統(tǒng)介紹USB接口波形發(fā)生器的設計。它采用直接數(shù)字頻率合成（DDFS）技術，實時將USB接收到的數(shù)據(jù)轉換成各種頻率的波形輸出，所使用的USB傳輸方式為全速同步傳輸。它可以輸出正鋸齒波、反鋸齒波、三角波、方波和正弦波5種波形。其硬件電路由以USB控制芯片AN2131QC為核心的USB接口單元、以可編程邏輯器件EPM7064為核心的DDFS單元、以數(shù)模轉換器TLC7524和DAC0832為核心的波形輸出單元三大部分構成。其中，USB接口單元負責完成硬件系統(tǒng)和PC機之間的數(shù)據(jù)傳輸，DDFS控制單元負責控制系統(tǒng)輸出波型的頻率，波形輸出單元負責對波形數(shù)據(jù)進行DA轉換，并負責控制輸出波形幅度峰峰值。它的系統(tǒng)軟件包括Keil C51語言編寫的AN2131QC芯片固件程序、Visual C++語言編寫的USB設備驅動程序和Win32應用程序。其波形頻率范圍是0.5Hz～15999.5Hz,步進值為0.5Hz，幅度范圍是0V～+5V,步進值為20mV。 關鍵詞: USB接口；任意波形；DDFS；波形發(fā)生器；Visual C++語言 ABSTRACT This system introduces the design of USB interface wave form generator. It uses direct digital frequency synthesizer (DDFS) techniques, real-time will be received USB data into various frequency waveform output, used for full-speed USB transfer mode asynchronous transfer. It can output is sawtooth, anti-aliasing wave, triangle wave, square wave and sine wave . The hardware circuit to USB controller chip by AN2131QC at the core of the USB interface unit to EPM7064 programmable logic device as the core unit DDFS to DAC TLC7524 and the DAC0832 output waveform at the core constitute the majority of unit three. Which, USB interface unit is responsible for the completion of the hardware systems and PC data transfer between machines, DDFS control unit control system is responsible for the frequency of the output waveform, waveform output unit is responsible for the waveform data DA conversion, and is responsible for control of output waveform peak-to-peak amplitude. Its system software, including the Keil C51 language AN2131QC firmware chip, Visual C + + language prepared USB device drivers and Win32 applications. It’s frequency adjustment range is 0.5Hz ~ 15999.5Hz, step value of 0.5Hz and amplitude of the adjustment range of 0V ~ +5 V, step value of 20mV. Key words: USB interface; Arbitrary Waveform; DDFS; waveform generator; Visual C+ + Language