{"resolved":true,"match_type":"uuid","source_type":"original_book","book_id":"38270854-596f-4a26-8183-db8c968c6020","title":"编码 隐匿在计算机软硬件背后的语言","author":null,"edition":null,"publisher":null,"year":null,"isbn":"9787121181184","requested_by":"printed_page","book":{"source_type":"original_book","book_id":"38270854-596f-4a26-8183-db8c968c6020","id":"38270854-596f-4a26-8183-db8c968c6020","uuid":"38270854-596f-4a26-8183-db8c968c6020","title":"编码 隐匿在计算机软硬件背后的语言","normalized_title":"编码隐匿在计算机软硬件背后的语言","author":null,"edition":null,"publisher":null,"year":null,"isbn":"9787121181184","isbns":["9787121181184","0123456789","6044921875","3039331000","0000000000","0000000000000"],"parsed":true,"ai_readable":true,"document_type":"book","page_count":438,"navigation_url":"https://workshop.closeclaw.top/ai/book/38270854-596f-4a26-8183-db8c968c6020","title_url":"https://workshop.closeclaw.top/ai/title/%E7%BC%96%E7%A0%81%20%E9%9A%90%E5%8C%BF%E5%9C%A8%E8%AE%A1%E7%AE%97%E6%9C%BA%E8%BD%AF%E7%A1%AC%E4%BB%B6%E8%83%8C%E5%90%8E%E7%9A%84%E8%AF%AD%E8%A8%80","fixed_page_url_template":"https://workshop.closeclaw.top/ai/book/38270854-596f-4a26-8183-db8c968c6020/page/{printed_page}","path_api_url_template":"https://workshop.closeclaw.top/api/ai/book/38270854-596f-4a26-8183-db8c968c6020/page/{printed_page}","read_url":"https://workshop.closeclaw.top/api/ai/read/38270854-596f-4a26-8183-db8c968c6020","page_url":"https://workshop.closeclaw.top/api/ai/books/38270854-596f-4a26-8183-db8c968c6020/page","search_url":"https://workshop.closeclaw.top/api/ai/books/38270854-596f-4a26-8183-db8c968c6020/search"},"page":{"printed_page":43,"pdf_page":59,"physical_index":59,"physical_index_base":0,"printed_page_status":"recognized","page_sha256":"7f34cee05935caa85cac847f39f7d82e28a0c5a1f279cb0debd44f3c5d0ce51b"},"chapter":"编码隐匿在计算机软硬件背后的语言","content":"当电报机的电键被按下时，发声器中的电磁铁拉动上面的活动横杠下降，它会发出“滴”的声音。当松开电键的时候，横杠弹回到原来的位置，发出“嗒”的声音。一次快速的“滴-嗒”声代表点；一次慢速的“滴嗒”声则代表划。\n\n电键、发声器、电池：还有一些导线连接到一起，电报机的电路示意图与前面章节中的手电筒电路图很相似。\n\n正如我们以前所发现的那样，不必非得用两根导线来连接两个电报站。如果地球能为我们提供电路的另一半的话，一根导线就足够了。\n\n就像我们在上一章所做的那样，我们可以把接地的电池用大写“V”表示。因此完整的单向系统如下图所示。\n\n双向通信仅仅需要再增加一个电键和发报人。这与我们前一章中的做法是类似的。\n\n电报机的发明标志着现代通信的开始。人们第一次能够在视线或者听力之外的距离范围进行实时交流了，而且信息传递的速度比骏马疾驰还要快。而更加耐人寻味的是，这个发明使用了二进制码。但是在后来的电子和无线通信（包括电话、无线电、电视）所使用的通信模式中，二进制码被废弃了，直到后来它又被应用在了电脑、光盘、数字\n\n6 电报机与继电器\n\n43","previous_page":42,"next_page":44}