{"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":278,"pdf_page":294,"physical_index":294,"physical_index_base":0,"printed_page_status":"recognized","page_sha256":"1498a7d9e4b1121331c69f80dc09eb052f635615e9d3bb0bfb866f91ead4098f"},"chapter":"编码隐匿在计算机软硬件背后的语言","content":"当然，你所看到的只是外部的封装。其内部的硅晶片是非常小的，例如在早期的8位微处理器中，硅晶片还不到1/4平方英寸。外包装可以保护内部的硅晶片，并且通过管脚提供了处理器的输入和输出访问接入点。下面给出了8080的40个管脚的功能说明图。\n\n本书中我们所创建的所有电气或电子设备都需要某种电源来供电。8080的一个特殊的地方就是它需要三种电源电压：管脚20必须接到5V的电压；管脚11需要接到-5V的电压；管脚28需接12V的电压；管脚2接地。（英特尔在1976年发布了8085芯片，目的就是简化对这些电源的要求)\n\n其他的管脚都标有箭头。从芯片引出的箭头表明这是一个输出（output）信号，这种信号由微处理器控制，计算机的其他芯片对该信号响应。指向芯片的箭头表明该信号是一个输入（input）信号，该信号由其他芯片发出，并由8080芯片对其响应。还一些管脚既是输入又是输出。\n\n第17章所设计的处理器需要一个振荡器来使其工作。8080需要两个不同的同步时钟输入，它们的频率都是2MHz，分别标记为 $\\phi$ 和 $\\phi _ { 2 }$ ，位于管脚22和15上。这些信号可以很方便地由英特尔生产的8224时钟信号发生器产生。为8224连接一个18MHz的石英晶体后，它基本上就可以完成其余工作了。\n\n一个微处理器通常有多个用来寻址存储器的输出信号。用于寻址的输出信号的数目与微处理器的可寻址空间大小直接相关。8080有16个用于寻址的输出信号，标记为 ${ \\bf A } _ { 0 } \\sim$ $\\mathbf { A } _ { 1 5 }$ ，因此它的可寻址空间大小为 $2 ^ { 1 6 }$ ，即65,536字节。\n\n编码隐匿在计算机软硬件背后的语言\n\n278","previous_page":277,"next_page":279}