【導(dǎo)讀】第二章方案比較與論證·····················5. 第三章系統(tǒng)模塊電路的設(shè)計···················7. 3.1系統(tǒng)總框圖········································································7. 3.2.1單片機最小系統(tǒng)模塊····················································7. 3.2.2時鐘電路模塊·····························································8. 3.2.3鍵盤模塊··································································11. 3.2.4顯示模塊··················································