นายรังสฤษดิ์ตั้งคณา รหัส นายวสันต์ ชานุชิต รหัส อาจารย์ที่ปรึกษาโครงการ ผศ. ดร. ดารณี หอมดี อาจารย์ที่ปรึกษาโครงการร่วม ดร. วาธิส ลีลาภัทร ดร. นวภัค เอื้ออนันต์
Introduction Electronic measure instrument Expensive Suitability Comfortable So we decided to designed something can be use as oscilloscope we call PC oscilloscope
Overview Soundcard have got 2 operations Recording Playback So we using soundcard on PC as oscilloscope Capture input signal and Display with recording Generate output signal with playback
Boundary of Project Soundcard Properties Sampling rate Bits/sample Software Boundary Time domain can not be show signal over 10 kHz Can be show sinusoidal signal only Can not be to knows voltage of signal
Solution Using Soundcard Wave API Directsound Make a Hardware Hardware to capture signal & sending data to PC Driver for Hardware Etc. Direct Access Memory (DMA)
Our Concepts Using Soundcard as hardware Wave API for capturing signal Directsound for generate signal Make a Hardware to protect soundcard Voltage devider
Hardware Designed Hardware Schematic
Software Designed Received signal module Block Diagram Signal from Hardware Microphone Channel Soundcard Received signal module Wave API Communication with soundcardDigital data from microphone channel
Software Designed (cont.) Generated signal module Block Diagram Generated signal module Wave API Soundcard Output Signal Headphone Channel Communication with soundcardDigital data to headphone channel
Implementation Hardware Hardware Box
Implementation (cont.) Software - Received signal module
Implementation (cont.) Software – Generated signal module
Testing & Result Signal Received
Testing & Result (cont.) Signal Generated
Conclusion Can be use soundcard as oscilloscope on boundary of soundcard and software Frequency not over 10 kHz Can be generate signal Sinusoidal,Square, Triangular, Sawtooth Can be knows frequency of signal Can’t be knows voltage of signal
Question?