{"id":25997,"date":"2022-04-03T19:21:29","date_gmt":"2022-04-03T12:21:29","guid":{"rendered":"https:\/\/tom.ji42.com\/?p=25997"},"modified":"2022-05-24T16:14:04","modified_gmt":"2022-05-24T09:14:04","slug":"%e0%b8%81%e0%b8%b2%e0%b8%a3%e0%b8%95%e0%b9%88%e0%b8%ad-rs232-%e0%b9%81%e0%b8%9a%e0%b8%9a-crossover-or-null-modem-%e0%b9%80%e0%b8%8a%e0%b8%b7%e0%b9%88%e0%b8%ad%e0%b8%a1-optimod","status":"publish","type":"post","link":"https:\/\/tom.tomwork.net\/?p=25997","title":{"rendered":"\u0e01\u0e32\u0e23\u0e15\u0e48\u0e2d RS232 \u0e41\u0e1a\u0e1a Crossover or Null Modem \u0e40\u0e0a\u0e37\u0e48\u0e2d\u0e21 Optimod"},"content":{"rendered":"<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p><b>\u0e01\u0e32\u0e23\u0e15\u0e48\u0e2d RS232 \u0e41\u0e1a\u0e1a Crossover or Null Modem \u0e40\u0e0a\u0e37\u0e48\u0e2d\u0e21 Optimod<\/b><\/p>\n<p><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o12.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"margin: 0px; display: inline; background-image: none;\" title=\"o1[2]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o12_thumb.jpg\" alt=\"o1[2]\" width=\"9\" height=\"9\" border=\"0\" \/><\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o2.jpg\"><br \/>\n<\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1514726183.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"border: 0px currentcolor; display: inline; background-image: none;\" title=\"pic1514726183\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1514726183_thumb.jpg\" alt=\"pic1514726183\" width=\"880\" height=\"659\" border=\"0\" \/><\/a><\/p>\n<p>\u0e40\u0e01\u0e47\u0e1a\u0e02\u0e49\u0e2d\u0e21\u0e39\u0e25\u0e44\u0e27\u0e49\u0e14\u0e39 \u0e01\u0e32\u0e23\u0e15\u0e48\u0e2d RS232 \u0e41\u0e1a\u0e1a Crossover or Null Modem\u00a0 \u0e43\u0e0a\u0e49\u0e23\u0e35\u0e42\u0e21\u0e17\u0e40\u0e0a\u0e37\u0e48\u0e2d\u0e21 Software \u0e01\u0e31\u0e1a Optimod 8400<\/p>\n<p><!--more--><\/p>\n<p><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o15.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"margin: 0px; display: inline; background-image: none;\" title=\"o1[5]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o15_thumb.jpg\" alt=\"o1[5]\" width=\"9\" height=\"9\" border=\"0\" \/><\/a><br \/>\n<a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1514726208.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"border: 0px currentcolor; display: inline; background-image: none;\" title=\"pic1514726208\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1514726208_thumb.jpg\" alt=\"pic1514726208\" width=\"586\" height=\"386\" border=\"0\" \/><\/a><\/p>\n<p><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o18.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"margin: 0px; display: inline; background-image: none;\" title=\"o1[8]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o18_thumb.jpg\" alt=\"o1[8]\" width=\"9\" height=\"9\" border=\"0\" \/><\/a><br \/>\n<a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic15147262351.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"border: 0px currentcolor; display: inline; background-image: none;\" title=\"pic1514726235[1]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic15147262351_thumb.jpg\" alt=\"pic1514726235[1]\" width=\"1079\" height=\"1613\" border=\"0\" \/><\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o42.jpg\"><br \/>\n<\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o23.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"margin: 0px; display: inline; background-image: none;\" title=\"o2[3]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o23_thumb.jpg\" alt=\"o2[3]\" width=\"16\" height=\"11\" border=\"0\" \/><\/a><\/p>\n<p><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o111.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"margin: 0px; display: inline; background-image: none;\" title=\"o1[11]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o111_thumb.jpg\" alt=\"o1[11]\" width=\"9\" height=\"9\" border=\"0\" \/><\/a><br \/>\n<a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1514726268.gif\"><img loading=\"lazy\" decoding=\"async\" style=\"border: 0px currentcolor; display: inline; background-image: none;\" title=\"pic1514726268\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1514726268_thumb.gif\" alt=\"pic1514726268\" width=\"558\" height=\"375\" border=\"0\" \/><\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o24.jpg\"><br \/>\n<\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic15147268481.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"border: 0px currentcolor; display: inline; background-image: none;\" title=\"pic1514726848[1]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic15147268481_thumb.jpg\" alt=\"pic1514726848[1]\" width=\"1079\" height=\"1099\" border=\"0\" \/><\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o24.jpg\"><br \/>\n<\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o34.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"margin: 0px; display: inline; background-image: none;\" title=\"o3[4]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o34_thumb.jpg\" alt=\"o3[4]\" width=\"16\" height=\"6\" border=\"0\" \/><\/a><\/p>\n<p><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o64.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"margin: 0px; display: inline; background-image: none;\" title=\"o6[4]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o64_thumb.jpg\" alt=\"o6[4]\" width=\"7\" height=\"16\" border=\"0\" \/><\/a><\/p>\n<p>A Null Modem or &#8220;crossover&#8221; cable is used to connect to DTE devices together. For this to work, the Transmit (TxD) pin of one device needs to be connected to the Receive (RxD) pin of the other device, and vice versa.<\/p>\n<p>To enable handshaking between the two devices, the Request to Send (RTS) pin of one device must be connected to the Clear to Send (CTS) pin of the other device, and the Data Set Ready (DSR) pin is connected to the Data Terminal Ready (DTR) pin of the other.<\/p>\n<p>Null modem adapters can also be used at the end of a straight-through serial cable to cross the lines. The StarTech SCNM9FF is an example of a null modem cable.<a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o25.jpg\"><br \/>\n<\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1514730155.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"border: 0px currentcolor; display: inline; background-image: none;\" title=\"pic1514730155\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1514730155_thumb.jpg\" alt=\"pic1514730155\" width=\"880\" height=\"658\" border=\"0\" \/><\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o27.jpg\"><br \/>\n<\/a><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1514994470.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"border: 0px currentcolor; display: inline; background-image: none;\" title=\"pic1514994470\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1514994470_thumb.jpg\" alt=\"pic1514994470\" width=\"880\" height=\"491\" border=\"0\" \/><\/a><\/p>\n<p>\u0e25\u0e31\u0e01\u0e29\u0e13\u0e30\u0e2b\u0e21\u0e32\u0e22\u0e40\u0e25\u0e02\u0e1b\u0e23\u0e30\u0e08\u0e33\u0e02\u0e32\u0e02\u0e31\u0e49\u0e27\u0e15\u0e48\u0e2d DB-9<\/p>\n<p><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o124.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"margin: 0px; display: inline; background-image: none;\" title=\"o1[24]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o124_thumb.jpg\" alt=\"o1[24]\" width=\"9\" height=\"9\" border=\"0\" \/><\/a><\/p>\n<p><a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o129.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"margin: 0px; display: inline; background-image: none;\" title=\"o1[29]\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/o129_thumb.jpg\" alt=\"o1[29]\" width=\"9\" height=\"9\" border=\"0\" \/><\/a><br \/>\n<a href=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1548078238.jpg\"><img loading=\"lazy\" decoding=\"async\" style=\"border: 0px currentcolor; display: inline; background-image: none;\" title=\"pic1548078238\" src=\"https:\/\/tom.tomwork.net\/wp-content\/uploads\/2022\/04\/pic1548078238_thumb.jpg\" alt=\"pic1548078238\" width=\"827\" height=\"1044\" border=\"0\" \/><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>&nbsp; &nbsp; \u0e01\u0e32\u0e23\u0e15\u0e48\u0e2d RS232 \u0e41\u0e1a\u0e1a Crossover or Null Modem \u0e40\u0e0a\u0e37\u0e48\u0e2d\u0e21 Optimod \u0e40\u0e01\u0e47\u0e1a\u0e02\u0e49\u0e2d\u0e21\u0e39\u0e25\u0e44\u0e27\u0e49\u0e14\u0e39 \u0e01\u0e32\u0e23\u0e15\u0e48\u0e2d RS232 \u0e41\u0e1a\u0e1a Crossover or Null Modem\u00a0 \u0e43\u0e0a\u0e49\u0e23\u0e35\u0e42\u0e21\u0e17\u0e40\u0e0a\u0e37\u0e48\u0e2d\u0e21 Software \u0e01\u0e31\u0e1a Optimod 8400<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[13],"tags":[],"class_list":["post-25997","post","type-post","status-publish","format-standard","hentry","category-13"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p6cOVM-6Lj","_links":{"self":[{"href":"https:\/\/tom.tomwork.net\/index.php?rest_route=\/wp\/v2\/posts\/25997","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tom.tomwork.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tom.tomwork.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tom.tomwork.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/tom.tomwork.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=25997"}],"version-history":[{"count":2,"href":"https:\/\/tom.tomwork.net\/index.php?rest_route=\/wp\/v2\/posts\/25997\/revisions"}],"predecessor-version":[{"id":26095,"href":"https:\/\/tom.tomwork.net\/index.php?rest_route=\/wp\/v2\/posts\/25997\/revisions\/26095"}],"wp:attachment":[{"href":"https:\/\/tom.tomwork.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=25997"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tom.tomwork.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=25997"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tom.tomwork.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=25997"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}