【導讀】課題設(shè)計的背景和意義·····································1. 主要設(shè)計內(nèi)容和要求·······································1. 第2章系統(tǒng)總體設(shè)計方案·············································2. 第3章硬件電路設(shè)計·················································4. 單片機最小系統(tǒng)··········································4. 超聲波發(fā)射電路···········································6. 超聲波檢測接收電路·······································7