{"id":412,"date":"2012-11-17T10:25:53","date_gmt":"2012-11-17T12:25:53","guid":{"rendered":"http:\/\/efagundes.com\/openclass_networking\/?page_id=412"},"modified":"2022-01-16T17:51:05","modified_gmt":"2022-01-16T20:51:05","slug":"transmissao-do-sinal-digital","status":"publish","type":"page","link":"https:\/\/efagundes.com\/networking\/sistema-telefonico\/transmissao-do-sinal-digital\/","title":{"rendered":"Transmiss\u00e3o do sinal digital"},"content":{"rendered":"<p><a href=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide104.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" data-attachment-id=\"2460\" data-permalink=\"https:\/\/efagundes.com\/networking\/sistema-telefonico\/transmissao-do-sinal-digital\/slide10-5\/\" data-orig-file=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide104.jpg?fit=960%2C720&amp;ssl=1\" data-orig-size=\"960,720\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"Slide10\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide104.jpg?fit=960%2C720&amp;ssl=1\" class=\"alignnone size-full wp-image-2460\" src=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide104.jpg?resize=960%2C720\" alt=\"Slide10\" width=\"960\" height=\"720\" srcset=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide104.jpg?w=960&amp;ssl=1 960w, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide104.jpg?resize=300%2C225&amp;ssl=1 300w\" sizes=\"auto, (max-width: 960px) 100vw, 960px\" \/><\/a>Dados digitais s\u00e3o informa\u00e7\u00f5es codificadas sob a forma de d\u00edgitos que podem assumir um certo n\u00famero de estados poss\u00edveis. Quando esses d\u00edgitos podem assumir dois estados, dizemos que s\u00e3o d\u00edgitos bin\u00e1rios ou \u201cbits\u201d ( \u201cBInary digiTS). Importante observar a exist\u00eancia de apenas dois estados poss\u00edveis para o bit, ou o bit \u00e9 1 ou \u00e9 0.<\/p>\n<p>Interligar duas m\u00e1quinas digitais \u00e9 fazer a transmiss\u00e3o de dados digitais entre elas. Basicamente, os dados podem ser transmitidos de duas forma: paralela ou serial. Na transmiss\u00e3o paralela, v\u00e1rios bits (um conjunto) s\u00e3o transmitidos simultaneamente. Na transmiss\u00e3o serial, os bits s\u00e3o transmitidos um ap\u00f3s o outro, o que exige apenas um par de fios.<\/p>\n<p>Na transmiss\u00e3o serial o conceito de sincronismo \u00e9 importante, devido ao fato que os bits chegam um ap\u00f3s o outro. Existe a necessidade do receptor saber quais bits pertencem a cada mensagem, normalmente codificadas em caracteres.<\/p>\n<p>A transmiss\u00e3o serial pode ser feita no modo s\u00edncrono ou ass\u00edncrono. No modo ass\u00edncrono, cada caractere do c\u00f3digo utilizado possui uma informa\u00e7\u00e3o de sincronismo pr\u00f3pria. A forma mais usual de se fazer inserir um bit de \u201cstart\u201d e um outro no final da seq\u00fc\u00eancia do caractere de \u201cstop\u201d.<\/p>\n<p>Na transmiss\u00e3o s\u00edncrono, um sinal espec\u00edfico de sincronismo deve ser transmitido junto com os dados, a fim de marcar o centro de cada bit para o receptor.<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Dados digitais s\u00e3o informa\u00e7\u00f5es codificadas sob a forma de d\u00edgitos que podem assumir um certo n\u00famero de estados poss\u00edveis. Quando esses d\u00edgitos podem assumir dois estados, dizemos que s\u00e3o d\u00edgitos bin\u00e1rios ou \u201cbits\u201d ( \u201cBInary digiTS). Importante observar a exist\u00eancia de apenas dois estados poss\u00edveis para o bit, ou o bit \u00e9 1 ou \u00e9 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":394,"menu_order":10,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-412","page","type-page","status-publish","hentry"],"jetpack_shortlink":"https:\/\/wp.me\/P8yKGp-6E","jetpack-related-posts":[{"id":146,"url":"https:\/\/efagundes.com\/networking\/modelos-de-referencia\/modelo-osi\/","url_meta":{"origin":412,"position":0},"title":"Modelo OSI","author":"Eduardo Fagundes","date":"16\/11\/2012","format":false,"excerpt":"As camadas 3, 2 e 1 s\u00e3o respons\u00e1veis por mover os pacotes de dados da esta\u00e7\u00e3o de origem para a esta\u00e7\u00e3o de destino. Camada Rede (3) A camada de rede estabelece a rota entre o transmissor e o receptor atrav\u00e9s dos pontos de roteamento existentes na rede. O exemplo mais\u2026","rel":"","context":"Post similar","block_context":{"text":"Post similar","link":""},"img":{"alt_text":"Slide2","src":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide210.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide210.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide210.jpg?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide210.jpg?resize=700%2C400 2x"},"classes":[]},{"id":414,"url":"https:\/\/efagundes.com\/networking\/sistema-telefonico\/modulacao-digital\/","url_meta":{"origin":412,"position":1},"title":"Modula\u00e7\u00e3o digital","author":"Eduardo Fagundes","date":"17\/11\/2012","format":false,"excerpt":"O sinal (bit) pode ser enviado basicamente de duas formas: digital e anal\u00f3gica. Para cada caso existem t\u00e9cnicas particulares a serem empregadas. A modula\u00e7\u00e3o constitui-se na t\u00e9cnica empregada para modificar um sinal com a finalidade de transportar uma informa\u00e7\u00e3o atrav\u00e9s do canal de comunica\u00e7\u00e3o e recuperar o sinal, na sua\u2026","rel":"","context":"Post similar","block_context":{"text":"Post similar","link":""},"img":{"alt_text":"Slide11","src":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide117.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide117.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide117.jpg?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide117.jpg?resize=700%2C400 2x"},"classes":[]},{"id":723,"url":"https:\/\/efagundes.com\/networking\/a-camada-de-rede\/a-camada-de-rede-2\/","url_meta":{"origin":412,"position":2},"title":"A Camada de Rede (I)","author":"Eduardo Fagundes","date":"18\/11\/2012","format":false,"excerpt":"O servi\u00e7o de rede prov\u00ea a transfer\u00eancia transparente de dados entre usu\u00e1rios da camada de rede. 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Como o tempo de transmiss\u00e3o de quadros n\u00e3o \u00e9 desprez\u00edvel, a ado\u00e7\u00e3o dessa t\u00e9cnica resulta, normalmente, em inefici\u00eancia. 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