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+--------+-------------------------+-------------------------+--------+--------+
|00000000| 46 72 6f 6d 20 63 68 72 | 69 73 40 63 68 72 69 73 |From chr|is@chris|
|00000010| 2e 74 65 6c 69 70 2e 75 | 6e 69 2d 73 62 2e 64 65 |.telip.u|ni-sb.de|
|00000020| 20 57 65 64 20 4d 61 72 | 20 20 31 20 31 37 3a 35 | Wed Mar|  1 17:5|
|00000030| 37 3a 31 38 20 31 39 39 | 35 0a 46 72 6f 6d 3a 20 |7:18 199|5.From: |
|00000040| 63 68 72 69 73 40 63 68 | 72 69 73 2e 74 65 6c 69 |chris@ch|ris.teli|
|00000050| 70 2e 75 6e 69 2d 73 62 | 2e 64 65 20 28 43 68 72 |p.uni-sb|.de (Chr|
|00000060| 69 73 20 42 6c 75 6d 29 | 0a 4e 65 77 73 67 72 6f |is Blum)|.Newsgro|
|00000070| 75 70 73 3a 20 63 6f 6d | 70 2e 73 79 73 2e 69 62 |ups: com|p.sys.ib|
|00000080| 6d 2e 70 63 2e 68 61 72 | 64 77 61 72 65 2e 63 6f |m.pc.har|dware.co|
|00000090| 6d 6d 2c 63 6f 6d 70 2e | 6f 73 2e 6d 73 64 6f 73 |mm,comp.|os.msdos|
|000000a0| 2e 70 72 6f 67 72 61 6d | 6d 65 72 0a 53 75 62 6a |.program|mer.Subj|
|000000b0| 65 63 74 3a 20 54 68 65 | 20 53 65 72 69 61 6c 20 |ect: The| Serial |
|000000c0| 50 6f 72 74 20 72 65 6c | 2e 20 31 38 2c 20 70 61 |Port rel|. 18, pa|
|000000d0| 72 74 20 31 2f 33 0a 44 | 61 74 65 3a 20 32 33 20 |rt 1/3.D|ate: 23 |
|000000e0| 46 65 62 20 31 39 39 35 | 20 30 30 3a 32 32 3a 30 |Feb 1995| 00:22:0|
|000000f0| 39 20 2b 30 31 30 30 0a | 4f 72 67 61 6e 69 7a 61 |9 +0100.|Organiza|
|00000100| 74 69 6f 6e 3a 20 54 68 | 65 20 4f 75 74 73 69 64 |tion: Th|e Outsid|
|00000110| 65 20 6f 66 20 74 68 65 | 20 41 73 79 6c 75 6d 0a |e of the| Asylum.|
|00000120| 52 65 70 6c 79 2d 54 6f | 3a 20 63 68 72 69 73 40 |Reply-To|: chris@|
|00000130| 70 68 69 6c 2e 75 6e 69 | 2d 73 62 2e 64 65 20 28 |phil.uni|-sb.de (|
|00000140| 43 68 72 69 73 20 42 6c | 75 6d 29 0a 4e 4e 54 50 |Chris Bl|um).NNTP|
|00000150| 2d 50 6f 73 74 69 6e 67 | 2d 48 6f 73 74 3a 20 63 |-Posting|-Host: c|
|00000160| 68 72 69 73 2e 74 65 6c | 69 70 2e 75 6e 69 2d 73 |hris.tel|ip.uni-s|
|00000170| 62 2e 64 65 0a 4b 65 79 | 77 6f 72 64 73 3a 20 63 |b.de.Key|words: c|
|00000180| 6f 6d 6d 2c 20 43 4f 4d | 2c 20 55 41 52 54 2c 20 |omm, COM|, UART, |
|00000190| 73 65 72 69 61 6c 20 70 | 6f 72 74 0a 0a 44 61 74 |serial p|ort..Dat|
|000001a0| 65 20 6f 66 20 72 65 6c | 65 61 73 65 3a 20 32 32 |e of rel|ease: 22|
|000001b0| 20 46 65 62 20 31 39 39 | 35 20 20 20 20 20 20 20 | Feb 199|5       |
|000001c0| 20 20 20 20 20 20 52 65 | 6c 65 61 73 65 20 31 38 |      Re|lease 18|
|000001d0| 0a 0a 54 68 69 73 20 69 | 73 20 61 20 73 75 6d 6d |..This i|s a summ|
|000001e0| 61 72 79 20 6f 6e 20 73 | 65 72 69 61 6c 20 63 6f |ary on s|erial co|
|000001f0| 6d 6d 75 6e 69 63 61 74 | 69 6f 6e 20 75 73 69 6e |mmunicat|ion usin|
|00000200| 67 20 74 68 65 20 54 54 | 59 20 70 72 6f 74 6f 63 |g the TT|Y protoc|
|00000210| 6f 6c 2e 20 49 74 0a 63 | 6f 6e 74 61 69 6e 73 20 |ol. It.c|ontains |
|00000220| 69 6e 66 6f 72 6d 61 74 | 69 6f 6e 20 6f 6e 20 74 |informat|ion on t|
|00000230| 68 65 20 54 54 59 20 70 | 72 6f 74 6f 63 6f 6c 20 |he TTY p|rotocol |
|00000240| 61 6e 64 20 68 61 72 64 | 77 61 72 65 20 61 6e 64 |and hard|ware and|
|00000250| 20 73 6f 66 74 77 61 72 | 65 20 69 6d 70 6c 65 6d | softwar|e implem|
|00000260| 65 6e 2d 0a 74 61 74 69 | 6f 6e 73 20 66 6f 72 20 |en-.tati|ons for |
|00000270| 49 42 4d 20 50 43 73 20 | 77 68 69 63 68 20 68 61 |IBM PCs |which ha|
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|00000290| 72 6f 6d 20 4e 61 74 69 | 6f 6e 61 6c 20 53 65 6d |rom Nati|onal Sem|
|000002a0| 69 63 6f 6e 64 75 63 74 | 6f 72 20 64 61 74 61 0a |iconduct|or data.|
|000002b0| 73 68 65 65 74 73 20 61 | 6e 64 20 70 72 61 63 74 |sheets a|nd pract|
|000002c0| 69 63 61 6c 20 65 78 70 | 65 72 69 65 6e 63 65 20 |ical exp|erience |
|000002d0| 6f 66 20 74 68 65 20 61 | 75 74 68 6f 72 20 61 6e |of the a|uthor an|
|000002e0| 64 20 68 69 73 20 73 75 | 70 70 6f 72 74 65 72 73 |d his su|pporters|
|000002f0| 2e 20 53 74 61 72 74 69 | 6e 67 0a 77 69 74 68 20 |. Starti|ng.with |
|00000300| 72 65 6c 65 61 73 65 20 | 35 2c 20 73 6f 6d 65 20 |release |5, some |
|00000310| 69 6e 66 6f 72 6d 61 74 | 69 6f 6e 20 6f 6e 20 6d |informat|ion on m|
|00000320| 6f 64 65 6d 73 20 68 61 | 73 20 62 65 65 6e 20 61 |odems ha|s been a|
|00000330| 64 64 65 64 2e 0a 0a 49 | 66 20 79 6f 75 20 77 61 |dded...I|f you wa|
|00000340| 6e 74 20 74 6f 20 63 6f | 6e 74 72 69 62 75 74 65 |nt to co|ntribute|
|00000350| 20 74 6f 20 74 68 69 73 | 20 66 69 6c 65 20 69 6e | to this| file in|
|00000360| 20 61 6e 79 20 77 61 79 | 2c 20 70 6c 65 61 73 65 | any way|, please|
|00000370| 20 65 6d 61 69 6c 20 6d | 65 20 28 70 72 6f 62 61 | email m|e (proba|
|00000380| 62 6c 79 0a 6a 75 73 74 | 20 72 65 70 6c 79 20 74 |bly.just| reply t|
|00000390| 6f 20 74 68 69 73 20 70 | 6f 73 74 69 6e 67 29 2e |o this p|osting).|
|000003a0| 20 4d 79 20 65 6d 61 69 | 6c 20 61 64 64 72 65 73 | My emai|l addres|
|000003b0| 73 20 69 73 3a 20 63 68 | 62 6c 40 73 74 75 64 2e |s is: ch|bl@stud.|
|000003c0| 75 6e 69 2d 73 62 2e 64 | 65 20 6f 72 0a 63 68 72 |uni-sb.d|e or.chr|
|000003d0| 69 73 40 70 68 69 6c 2e | 75 6e 69 2d 73 62 2e 64 |is@phil.|uni-sb.d|
|000003e0| 65 2e 20 53 65 65 20 74 | 68 65 20 65 6e 64 20 66 |e. See t|he end f|
|000003f0| 6f 72 20 64 65 74 61 69 | 6c 73 2e 0a 0a 49 74 27 |or detai|ls...It'|
|00000400| 73 20 74 68 65 20 73 65 | 76 65 6e 74 65 65 6e 74 |s the se|venteent|
|00000410| 68 20 70 75 62 6c 69 63 | 61 74 69 6f 6e 20 6f 66 |h public|ation of|
|00000420| 20 74 68 69 73 20 66 69 | 6c 65 2e 20 53 6f 6d 65 | this fi|le. Some|
|00000430| 20 65 72 72 6f 72 73 20 | 68 61 76 65 20 62 65 65 | errors |have bee|
|00000440| 6e 20 63 6f 72 72 65 63 | 74 65 64 0a 61 6e 64 20 |n correc|ted.and |
|00000450| 73 6f 6d 65 20 69 6e 66 | 6f 72 6d 61 74 69 6f 6e |some inf|ormation|
|00000460| 20 68 61 73 20 62 65 65 | 6e 20 61 64 64 65 64 20 | has bee|n added |
|00000470| 28 77 68 69 63 68 20 68 | 61 73 20 73 75 72 65 6c |(which h|as surel|
|00000480| 79 20 62 72 6f 75 67 68 | 74 20 6f 74 68 65 72 20 |y brough|t other |
|00000490| 65 72 72 6f 72 73 0a 77 | 69 74 68 20 69 74 2c 20 |errors.w|ith it, |
|000004a0| 73 65 65 20 4d 75 72 70 | 68 79 27 73 20 4c 61 77 |see Murp|hy's Law|
|000004b0| 29 2e 0a 0a 5b 5d 20 62 | 72 61 63 6b 65 74 73 20 |)...[] b|rackets |
|000004c0| 6f 66 74 65 6e 20 69 6e | 64 69 63 61 74 65 20 63 |often in|dicate c|
|000004d0| 6f 6d 6d 65 6e 74 73 20 | 74 6f 20 73 6e 65 61 6b |omments |to sneak|
|000004e0| 65 64 20 6d 61 74 65 72 | 69 61 6c 3b 20 63 6f 70 |ed mater|ial; cop|
|000004f0| 69 65 64 20 6c 69 6e 65 | 73 20 61 72 65 0a 69 6e |ied line|s are.in|
|00000500| 64 65 6e 74 65 64 2e 20 | 49 27 76 65 20 6d 61 64 |dented. |I've mad|
|00000510| 65 20 67 72 65 61 74 20 | 65 66 66 6f 72 74 73 20 |e great |efforts |
|00000520| 74 6f 20 61 6c 77 61 79 | 73 20 6d 65 6e 74 69 6f |to alway|s mentio|
|00000530| 6e 20 77 68 6f 27 73 20 | 74 6f 20 62 65 20 63 72 |n who's |to be cr|
|00000540| 65 64 69 74 65 64 2e 0a | 50 6c 65 61 73 65 20 74 |edited..|Please t|
|00000550| 65 6c 6c 20 6d 65 20 69 | 66 20 79 6f 75 20 66 69 |ell me i|f you fi|
|00000560| 6e 64 20 73 6f 6d 65 74 | 68 69 6e 67 20 74 68 61 |nd somet|hing tha|
|00000570| 74 20 79 6f 75 27 76 65 | 20 77 72 69 74 74 65 6e |t you've| written|
|00000580| 20 74 68 61 74 27 73 20 | 6e 6f 74 20 63 6f 72 72 | that's |not corr|
|00000590| 65 63 74 6c 79 0a 61 73 | 73 6f 63 69 61 74 65 64 |ectly.as|sociated|
|000005a0| 20 77 69 74 68 20 79 6f | 75 72 20 6e 61 6d 65 2e | with yo|ur name.|
|000005b0| 0a 0a 54 68 69 73 20 63 | 6f 6d 70 69 6c 61 74 69 |..This c|ompilati|
|000005c0| 6f 6e 20 6f 66 20 69 6e | 66 6f 72 6d 61 74 69 6f |on of in|formatio|
|000005d0| 6e 20 69 73 20 28 43 29 | 20 43 6f 70 79 72 69 67 |n is (C)| Copyrig|
|000005e0| 68 74 20 31 39 39 33 20 | 2d 20 31 39 39 35 20 62 |ht 1993 |- 1995 b|
|000005f0| 79 20 43 68 72 69 73 74 | 69 61 6e 0a 42 6c 75 6d |y Christ|ian.Blum|
|00000600| 3b 20 61 6c 6c 20 72 69 | 67 68 74 73 20 72 65 73 |; all ri|ghts res|
|00000610| 65 72 76 65 64 2e 20 54 | 68 69 73 20 66 69 6c 65 |erved. T|his file|
|00000620| 20 69 73 20 6e 6f 74 20 | 74 6f 20 62 65 20 72 65 | is not |to be re|
|00000630| 70 72 6f 64 75 63 65 64 | 20 63 6f 6d 6d 65 72 63 |produced| commerc|
|00000640| 69 61 6c 6c 79 2c 0a 6e | 6f 74 20 65 76 65 6e 20 |ially,.n|ot even |
|00000650| 70 61 72 74 69 61 6c 6c | 79 2c 20 77 69 74 68 6f |partiall|y, witho|
|00000660| 75 74 20 77 72 69 74 74 | 65 6e 20 70 65 72 6d 69 |ut writt|en permi|
|00000670| 73 73 69 6f 6e 2e 20 59 | 6f 75 20 61 72 65 20 61 |ssion. Y|ou are a|
|00000680| 6c 6c 6f 77 65 64 20 74 | 6f 20 75 73 65 20 69 74 |llowed t|o use it|
|00000690| 0a 69 6e 20 61 6e 79 20 | 6f 74 68 65 72 20 77 61 |.in any |other wa|
|000006a0| 79 20 79 6f 75 20 6c 69 | 6b 65 2e 20 49 20 64 6f |y you li|ke. I do|
|000006b0| 6e 27 74 20 77 61 6e 74 | 20 61 6e 79 20 28 6d 6f |n't want| any (mo|
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|000006d0| 65 69 6e 67 20 64 72 61 | 77 6e 0a 6f 75 74 20 6f |eing dra|wn.out o|
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|000006f0| 20 6d 65 20 6e 6f 72 20 | 62 79 20 6f 74 68 65 72 | me nor |by other|
|00000700| 73 21 20 49 20 64 6f 6e | 27 74 20 6d 69 6e 64 20 |s! I don|'t mind |
|00000710| 69 66 20 79 6f 75 20 68 | 61 76 65 20 61 20 6c 6f |if you h|ave a lo|
|00000720| 6f 6b 0a 6f 72 20 74 77 | 6f 20 61 74 20 69 74 20 |ok.or tw|o at it |
|00000730| 61 74 20 77 6f 72 6b 20 | 74 68 6f 75 67 68 2e 2e |at work |though..|
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|00000770| 6f 74 68 65 72 73 20 66 | 6f 72 20 66 72 65 65 20 |others f|or free |
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|00000800| 6e 6f 77 6c 65 64 67 69 | 6e 67 20 69 6e 20 74 68 |nowledgi|ng in th|
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|00000830| 73 75 67 67 65 73 74 65 | 64 20 73 6f 6d 65 20 63 |suggeste|d some c|
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|00000900| 3d 0a 0a 49 27 6d 20 6e | 6f 20 6c 6f 6e 67 65 72 |=..I'm n|o longer|
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|00000950| 73 6f 20 64 6f 6e 27 74 | 20 65 78 70 65 63 74 20 |so don't| expect |
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|00000990| 74 69 6e 67 20 74 68 69 | 73 0a 74 6f 2e 0a 0a 0a |ting thi|s.to....|
|000009a0| 57 68 61 74 20 6f 74 68 | 65 72 73 20 61 72 65 20 |What oth|ers are |
|000009b0| 64 6f 69 6e 67 0a 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |doing.==|========|
|000009c0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 0a 0a 54 68 65 |========|===..The|
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|00000a70| 6f 6e 20 75 6e 64 65 72 | 20 57 69 6e 64 6f 77 73 |on under| Windows|
|00000a80| 2e 20 49 74 20 69 73 20 | 72 65 67 75 6c 61 72 6c |. It is |regularl|
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|00000b40| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
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|00000b90| 6d 65 6e 74 69 6f 6e 65 | 64 20 69 6e 20 65 61 72 |mentione|d in ear|
|00000ba0| 6c 69 65 72 20 72 65 6c | 65 61 73 65 73 20 6f 66 |lier rel|eases of|
|00000bb0| 0a 74 68 69 73 20 66 69 | 6c 65 20 69 73 20 73 74 |.this fi|le is st|
|00000bc0| 69 6c 6c 20 61 76 61 69 | 6c 61 62 6c 65 2c 20 62 |ill avai|lable, b|
|00000bd0| 75 74 20 49 20 77 6f 6e | 27 74 20 64 6f 20 61 6e |ut I won|'t do an|
|00000be0| 79 74 68 69 6e 67 20 74 | 6f 20 6b 65 65 70 20 69 |ything t|o keep i|
|00000bf0| 74 0a 61 6c 69 76 65 20 | 66 72 6f 6d 20 6e 6f 77 |t.alive |from now|
|00000c00| 20 6f 6e 2e 20 50 6c 65 | 61 73 65 20 6f 62 74 61 | on. Ple|ase obta|
|00000c10| 69 6e 20 74 68 65 20 66 | 69 6c 65 73 20 76 69 61 |in the f|iles via|
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|00000c40| 2d 73 62 2e 64 65 20 28 | 31 33 34 2e 39 36 2e 38 |-sb.de (|134.96.8|
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|00000c60| 66 2f 63 68 72 69 73 2e | 0a 0a 49 66 20 79 6f 75 |f/chris.|..If you|
|00000c70| 20 64 6f 6e 27 74 20 68 | 61 76 65 20 61 63 63 65 | don't h|ave acce|
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|00000c90| 73 69 6e 67 20 61 6e 20 | 66 74 70 20 74 6f 20 65 |sing an |ftp to e|
|00000ca0| 6d 61 69 6c 20 67 61 74 | 65 77 61 79 0a 28 66 74 |mail gat|eway.(ft|
|00000cb0| 70 6d 61 69 6c 40 64 65 | 63 77 72 6c 2e 64 65 63 |pmail@de|cwrl.dec|
|00000cc0| 2e 63 6f 6d 20 6f 72 20 | 62 69 74 66 74 70 40 70 |.com or |bitftp@p|
|00000cd0| 75 63 63 2e 70 72 69 6e | 63 65 74 6f 6e 2e 65 64 |ucc.prin|ceton.ed|
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|00000cf0| 61 20 6c 6f 74 20 6d 6f | 72 65 3b 20 70 75 74 20 |a lot mo|re; put |
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|00000d30| 76 65 72 79 74 68 69 6e | 67 0a 66 61 69 6c 73 2c |verythin|g.fails,|
|00000d40| 20 77 72 69 74 65 20 74 | 6f 20 6d 65 2e 0a 0a 0a | write t|o me....|
|00000d50| 41 63 6b 6e 6f 77 6c 65 | 64 67 65 6d 65 6e 74 73 |Acknowle|dgements|
|00000d60| 20 20 20 28 71 75 69 74 | 65 20 61 20 62 75 6e 63 |   (quit|e a bunc|
|00000d70| 68 20 6f 66 20 70 65 6f | 70 6c 65 20 62 79 20 6e |h of peo|ple by n|
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|00004eb0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004ec0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004ed0| 2d 2d 2d 0a 20 20 20 20 | 20 20 20 20 31 31 30 20 |---.    |    110 |
|00004ee0| 20 20 20 20 20 20 7c 20 | 20 20 20 20 20 35 30 30 |      | |     500|
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|00004f40| 20 20 31 32 30 30 20 20 | 20 20 20 20 7c 20 20 20 |  1200  |    |   |
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|00004f80| 20 20 20 20 20 20 31 30 | 30 30 66 74 20 20 20 20 |      10|00ft    |
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|00004fa0| 20 20 20 20 20 20 20 34 | 38 30 30 20 20 20 20 20 |       4|800     |
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|00005310| 73 74 20 68 61 76 65 20 | 74 6f 20 74 72 79 20 61 |st have |to try a|
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|00005340| 0a 0a 0a 0a 48 61 72 64 | 77 61 72 65 0a 3d 3d 3d |....Hard|ware.===|
|00005350| 3d 3d 3d 3d 3d 0a 0a 0a | 54 68 65 20 63 6f 6e 6e |=====...|The conn|
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|00005370| 2d 2d 2d 2d 2d 0a 0a 50 | 43 73 20 68 61 76 65 20 |-----..P|Cs have |
|00005380| 39 70 69 6e 2f 32 35 70 | 69 6e 20 6d 61 6c 65 20 |9pin/25p|in male |
|00005390| 53 55 42 2d 44 20 63 6f | 6e 6e 65 63 74 6f 72 73 |SUB-D co|nnectors|
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|00005410| 20 20 20 20 35 0a 20 20 | 20 20 20 20 5f 5f 5f 5f |    5.  |    ____|
|00005420| 5f 5f 5f 5f 5f 5f 5f 5f | 5f 5f 5f 5f 5f 5f 5f 5f |________|________|
|00005430| 5f 5f 5f 5f 5f 5f 5f 5f | 5f 5f 5f 20 20 20 20 20 |________|___     |
|00005440| 20 5f 5f 5f 5f 5f 5f 5f | 5f 5f 5f 5f 5f 5f 5f 5f | _______|________|
|00005450| 0a 20 20 20 20 20 20 5c | 20 20 2e 20 2e 20 2e 20 |.      \|  . . . |
|00005460| 2e 20 2e 20 2e 20 2e 20 | 2e 20 2e 20 2e 20 2e 20 |. . . . |. . . . |
|00005470| 2e 20 2e 20 20 2f 20 20 | 20 20 20 20 5c 20 20 2e |. .  /  |    \  .|
|00005480| 20 2e 20 2e 20 2e 20 2e | 20 20 2f 0a 20 20 20 20 | . . . .|  /.    |
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|000054a0| 2e 20 2e 20 2e 20 2e 20 | 2e 20 2e 20 2e 20 20 2f |. . . . |. . .  /|
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|000054d0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000054e0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 20 20 20 20 20 20 20 |--------|-       |
|000054f0| 20 20 20 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 0a 20 |   -----|------. |
|00005500| 20 20 20 20 20 20 20 31 | 34 20 20 20 20 20 20 20 |       1|4       |
|00005510| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|00005520| 32 35 20 20 20 20 20 20 | 20 20 20 20 20 36 20 20 |25      |     6  |
|00005530| 20 20 20 20 20 39 0a 0a | 20 4e 61 6d 65 20 28 56 |     9..| Name (V|
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|00005550| 20 20 44 69 72 20 20 46 | 75 6c 6c 20 6e 61 6d 65 |  Dir  F|ull name|
|00005560| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 52 |        |       R|
|00005570| 65 6d 61 72 6b 73 0a 2d | 2d 2d 2d 2d 2d 2d 2d 2d |emarks.-|--------|
|00005580| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00005590| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000055a0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000055b0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000055c0| 2d 0a 20 20 20 20 54 78 | 44 20 20 20 20 20 20 20 |-.    Tx|D       |
|000055d0| 20 20 32 20 20 20 20 20 | 33 20 20 20 20 6f 20 20 |  2     |3    o  |
|000055e0| 20 54 72 61 6e 73 6d 69 | 74 20 44 61 74 61 20 20 | Transmi|t Data  |
|000055f0| 20 20 20 20 20 20 20 20 | 20 44 61 74 61 0a 20 20 |        | Data.  |
|00005600| 20 20 52 78 44 20 20 20 | 20 20 20 20 20 20 33 20 |  RxD   |      3 |
|00005610| 20 20 20 20 32 20 20 20 | 20 69 20 20 20 52 65 63 |    2   | i   Rec|
|00005620| 65 69 76 65 20 44 61 74 | 61 20 20 20 20 20 20 20 |eive Dat|a       |
|00005630| 20 20 20 20 20 44 61 74 | 61 0a 20 20 20 20 52 54 |     Dat|a.    RT|
|00005640| 53 20 20 20 20 20 20 20 | 20 20 34 20 20 20 20 20 |S       |  4     |
|00005650| 37 20 20 20 20 6f 20 20 | 20 52 65 71 75 65 73 74 |7    o  | Request|
|00005660| 20 54 6f 20 53 65 6e 64 | 20 20 20 20 20 20 20 20 | To Send|        |
|00005670| 20 48 61 6e 64 73 68 61 | 6b 69 6e 67 0a 20 20 20 | Handsha|king.   |
|00005680| 20 43 54 53 20 20 20 20 | 20 20 20 20 20 35 20 20 | CTS    |     5  |
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|000056c0| 20 20 20 20 44 54 52 20 | 20 20 20 20 20 20 20 32 |    DTR |       2|
|000056d0| 30 20 20 20 20 20 34 20 | 20 20 20 6f 20 20 20 44 |0     4 |   o   D|
|000056e0| 61 74 61 20 54 65 72 6d | 69 6e 61 6c 20 52 65 61 |ata Term|inal Rea|
|000056f0| 64 79 20 20 20 20 20 53 | 74 61 74 75 73 0a 20 20 |dy     S|tatus.  |
|00005700| 20 20 44 53 52 20 20 20 | 20 20 20 20 20 20 36 20 |  DSR   |      6 |
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|00005740| 52 49 20 20 20 20 20 20 | 20 20 20 32 32 20 20 20 |RI      |   22   |
|00005750| 20 20 39 20 20 20 20 69 | 20 20 20 52 69 6e 67 20 |  9    i|   Ring |
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|000057b0| 20 53 74 61 74 75 73 0a | 20 20 20 20 47 4e 44 20 | Status.|    GND |
|000057c0| 20 20 20 20 20 20 20 20 | 37 20 20 20 20 20 35 20 |        |7     5 |
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|00005820| 6f 74 65 63 74 69 76 65 | 20 67 72 6f 75 6e 64 20 |otective| ground |
|00005830| 20 20 20 20 20 20 44 6f | 6e 27 74 20 75 73 65 20 |      Do|n't use |
|00005840| 74 68 69 73 20 6f 6e 65 | 0a 20 20 20 20 20 20 20 |this one|.       |
|00005850| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|00005860| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|00005870| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
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|000058d0| 65 64 20 77 69 74 68 0a | 6d 6f 64 65 6d 73 2c 20 |ed with.|modems, |
|000058e0| 70 72 69 6e 74 65 72 73 | 20 61 6e 64 20 70 6c 6f |printers| and plo|
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|00005910| 73 2e 0a 0a 27 31 27 20 | 28 27 6d 61 72 6b 27 2c |s...'1' |('mark',|
|00005920| 20 27 6c 6f 77 27 29 20 | 6d 65 61 6e 73 20 2d 33 | 'low') |means -3|
|00005930| 76 20 74 6f 20 2d 31 35 | 76 2c 20 27 30 27 20 28 |v to -15|v, '0' (|
|00005940| 27 73 70 61 63 65 27 2c | 20 27 68 69 67 68 27 29 |'space',| 'high')|
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|00005990| 20 73 74 61 74 75 73 20 | 6c 69 6e 65 73 20 67 6f | status |lines go|
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|000059b0| 20 76 6f 6c 74 61 67 65 | 20 6c 65 76 65 6c 20 74 | voltage| level t|
|000059c0| 6f 20 73 69 67 6e 61 6c | 20 65 76 65 6e 74 73 2e |o signal| events.|
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|000059e0| 0a 0a 20 20 52 78 44 2c | 20 54 78 44 3a 20 54 68 |..  RxD,| TxD: Th|
|000059f0| 65 73 65 20 6c 69 6e 65 | 73 20 63 61 72 72 79 20 |ese line|s carry |
|00005a00| 74 68 65 20 64 61 74 61 | 3b 20 31 20 69 73 20 74 |the data|; 1 is t|
|00005a10| 72 61 6e 73 6d 69 74 74 | 65 64 20 61 73 20 27 6d |ransmitt|ed as 'm|
|00005a20| 61 72 6b 27 20 28 77 68 | 61 74 20 49 0a 20 20 20 |ark' (wh|at I.   |
|00005a30| 20 63 61 6c 6c 20 27 6c | 6f 77 27 29 20 61 6e 64 | call 'l|ow') and|
|00005a40| 20 30 20 69 73 20 74 72 | 61 6e 73 6d 69 74 74 65 | 0 is tr|ansmitte|
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|00005a60| 69 67 68 27 29 2e 0a 0a | 20 20 52 54 53 2c 20 43 |igh')...|  RTS, C|
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|00005a90| 6f 64 65 6d 2f 70 72 69 | 6e 74 65 72 2f 77 68 61 |odem/pri|nter/wha|
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|00005ab0| 0a 20 20 20 20 6f 6e 20 | 72 65 66 65 72 72 65 64 |.    on |referred|
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|00005ae0| 73 74 61 72 74 2f 73 74 | 6f 70 20 61 20 63 6f 6d |start/st|op a com|
|00005af0| 6d 75 6e 69 63 61 74 69 | 6f 6e 2e 0a 20 20 20 20 |municati|on..    |
|00005b00| 54 68 65 20 50 43 20 73 | 65 74 73 20 52 54 53 20 |The PC s|ets RTS |
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|00005b80| 69 6e 74 65 72 72 75 70 | 74 20 74 68 65 0a 20 20 |interrup|t the.  |
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|00005bd0| 27 6c 6f 77 27 3b 0a 20 | 20 20 20 74 68 65 20 50 |'low';. |   the P|
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|00005d10| 65 73 65 74 74 69 6e 67 | 20 44 53 52 20 74 6f 20 |esetting| DSR to |
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|00005d40| 67 20 75 70 20 62 79 20 | 64 72 6f 70 70 69 6e 67 |g up by |dropping|
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|00005d70| 47 4e 44 20 61 72 65 20 | 6f 66 74 65 6e 20 72 65 |GND are |often re|
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|00005dc0| 0a 20 20 44 43 44 3a 20 | 54 68 65 20 6d 6f 64 65 |.  DCD: |The mode|
|00005dd0| 6d 20 75 73 65 73 20 74 | 68 69 73 20 6c 69 6e 65 |m uses t|his line|
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|00005e40| 6e 65 2e 20 54 68 65 20 | 73 69 67 6e 61 6c 20 69 |ne. The |signal i|
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|00005ee0| 74 6f 20 79 6f 75 72 20 | 6d 6f 64 65 6d 20 6e 6f |to your |modem no|
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|00005fc0| 20 61 73 20 61 20 73 69 | 67 6e 61 6c 20 67 72 6f | as a si|gnal gro|
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|00005ff0| 65 63 74 65 64 20 74 6f | 20 47 4e 44 20 28 65 76 |ected to| GND (ev|
|00006000| 65 6e 20 69 66 20 79 6f | 75 72 20 44 4d 4d 20 5b |en if yo|ur DMM [|
|00006010| 44 69 67 69 74 61 6c 20 | 4d 75 6c 74 69 4d 65 74 |Digital |MultiMet|
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|000060a0| 20 67 72 6f 75 6e 64 20 | 6f 6e 20 62 6f 74 68 20 | ground |on both |
|000060b0| 73 69 64 65 73 20 6d 61 | 6b 65 73 20 73 75 72 65 |sides ma|kes sure|
|000060c0| 20 74 68 61 74 0a 20 20 | 20 20 6e 6f 20 6c 61 72 | that.  |  no lar|
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|00006230| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
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+--------+-------------------------+-------------------------+--------+--------+