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Сети и телекоммуникации

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PEP, HST, V.FC, x2, K56Flex;

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V.42, V.42bis;

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— bf_ggh \ wlhf jZa^_e_ Ihijhklm ]h\hjy y ihevamxkv a^_kv qbklh ijZdlbq_kdbf hij_^_e_-

gb_f keh\Z©ijhlhdheª ©lh qlh ^he`gh kh\iZ^Zlv m fh^_fh\ b dhfivxl_jh\ gZ h[hbo dhgpZo ebgbb qlh[u h[_ki_qb\Zehkv \aZbfhihgbfZgb_ b hlkmlkl\b_ bkdZ`_gbcª

Fbj klZg^Zjlh\

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Gh ih`Zemc kZfu_ \Z`gu_ ^ey fh^_fZ klZg^Zjlu — l_ qlh hij_^_eyxl kdhjhklv _]h jZ[hlu b f_lh^ fh^meypbb < gZklhys__ \j_fy wlb klZg^Zjlu mklZgZ\eb\Zxlky k_dlhjhf klZg^ZjlbaZpbb l_e_dhffmgbdZpbc F_`^mgZjh^gh]h l_e_dhffmgbdZpbhggh]h khxaZ

Zg]e ITU-T, International Telecommunication Union — Telecommunication Standardization Sector1). JZkiheh`_gguc \ @_g_\_

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« terboª lZd \ke_^ aZ V ihy\bebkv V.26bis b V.26terbo,

^hihegyxsb_ b jZa\b\Zxsb_ bkoh^guc klZg^Zjl Wlb klZg^Zjlu ho\Zlu\Zxl kZfuc rbjhdbc djm] \hijhkh\

gZijbf_j V ij_^klZ\ey_l kh[hc kibkhd l_jfbgh\ ba h[eZklb pbnjh\hc k\yab gZ lj_o yaudZo Zg]ebckdhf njZgpmakdhf b bkiZgkdhf V hij_^_ey_l i_j_^Zqm ih l_e_nhgghc ebgbb f_^b- pbgkdbo we_dljhdZj^bh]jZff Z klZg^Zjl V.I mklZgZ\eb\Z_l iZjZf_lju i_j_^Zqb nZdkbfbevgh]h bah[jZ`_gby gZ kdhjhklb ^h

D[bl k AgZqbl_evgh_ qbkeh klZg^Zjlh\ V.xx ihk\ys_gh fh^_fghc k\yab

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>jm]Zy \Z`gZy ]jmiiZ klZg^Zjlh\ — ijhlhdheu dhjj_dpbb hrb[hd b k`Zlby ^Zgguo iha\heyxsb_ aZf_lgh ih\ukblv dZq_kl\h k\yab gZ lhc `_ kZfhc kdhjhklb A^_kv \Z`gZy jhev ijbgZ^e_`bl nbjf_ Microcom dhlhjZy j_Zebah\ZeZ \ k\hbo fh^_fZo k_jbx ijhlhdheh\ MNP (Microcom Networking Protocol ©K_l_\hc ijhlhdhe

0LFURFRPª Wlb ijhlhdheu b k_cqZk jZkijhkljZg_gu ^hklZlhqgh rbjhdh ohly b hlhreb gZ \lhjhc ieZg k ihy\e_gb_f klZg^Zjlh\ ITU- T V b V.42bis.

DhffmgbdZpbhggu_ iZjZf_lju

IZjZf_lju dhlhju_ ijbgylh gZau\Zlv dhffmgbdZpbhggufb

(communication settings, line settings hij_^_eyxl qlh ijhbkoh^bl k ^Zggufb _s_ ^h lh]h dZd hgb ihiZ^Zxl \ fh^_f >_eh \ lhf qlh jZa[b_gb_ bgnhjfZpbb — kiehrgh]h ihlhdZ [blh\ — gZ hl^_evgu_ [ehdb lh _klv kbgojhggh-Zkbgojhggh_ ij_h[jZah\Zgb_ klj , ijhba\h^blky \ dhfivxl_j_ \k_]^Z dh]^Z wlZ bgnhjfZpby ihkueZ_lky gZ ihke_^h\Zl_evguc ihjl gZijbf_j KHF beb&20 Ihwlhfm fh^_f dZd b ex[h_ ^jm]h_ mkljhckl\h ih^dexq_ggh_ d ihke_^h\Zl_evghfm ihjlm ihemqZ_l ^Zggu_ bf_ggh \ lZdhf f_edh gZj_aZgghf \b^_

>ey wlh]h ij_h[jZah\Zgby \ dhfivxl_j_ _klv ki_pbZevgZy fbdjhko_fZ gZau\Z_fZy UART (Universal Asynchronous Receiver Transmitter ©Mgb\_jkZevguc Zkbgojhgguc ijb_fh-i_j_^Zl-qbdª Wlhl qbi k\yaZgguc k dhfivxl_jhf iZjZee_evgh Z k

ihjlZfb — ihke_^h\Zl_evgh h[kem`b\Z_l lhevdh bf_xsb_ky \ dhfivxl_j_ ihke_^h\Zl_evgu_ ihjlu ihwlhfm \gmlj_ggbc fh^_fklj dhlhjuc©kZf k_[_ ihjlª\ mkem]Zo UART g_ gm`^Z_lky — hg ij_h[jZam_l ^Zggu_ \ Zkbgojhgguc nhjfZl kZfhklhyl_evgh

Kbgojhggh-Zkbgojhgghfm ij_h[jZah\Zgbx ihk\ys_g hl^_evguc klZg^Zjl ITU-T Z bf_ggh V beb qlh lh `_ kZfh_ Zkbgojhgguc ijhlhdhe RSQlh `_ ijhbkoh^bl ijb wlhf k ^Zggufb"

KlZjlh\u_ klhih\u_ b dhgljhevgu_ [blu

Ij_`^_ \k_]h ^Zggu_ ij_h[jZamxlky \ ihke_^h\Zl_evguc nhjfZl lh _klv \ kiehrgmx p_ihqdm [blh\ AZl_f qlh[u ^Zggu_ fh`gh [ueh i_j_^Z\Zlv Zkbgojhggh wlZ p_ihqdZ jZa[b\Z_lky gZ [ehdb dhlhju_ \ ^Zgghf kemqZ_ jZ\gu h^ghfm [Zclm B gZdhg_p dZ`^uc [ehd kgZ[`Z_lky fZjd_jZfb — ijbagZdZfb gZqZeZ b dhgpZ [ehdZ

< 9 wlbfb fZjd_jZfb y\eyxlky klZjlh\uc [bl (start bit b klhih\uc [bl (stop bit KlZjlh\uc [bl \k_]^Z jZ\_g H klhih\uc —

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LZdhc f_oZgbaf h[_ki_qb\Z_l ]b[dbc dhglZdl i_j_^ZlqbdZ b ijb_fgbdZ gh g_ aZsbsZ_l hl hrb[hd dhlhju_ fh]ml ijhbahclb ijb i_j_^Zq_ Qlh[u h[_ki_qblv h[gZjm`_gb_ hrb[hd klZg^Zjl 9 ij_^ibku\Z_l \klZ\dm kjZam ihke_ [ZclZ ^Zgguo i_j_^ klhih\uf [blhf _s_ h^gh]h [blZ — dhgljhevgh]h (parity bit ?]h agZq_gb_ hij_^_ey_lky kh^_j`bfuf i_j_^Z\Z_fh]h [ZclZ b l_f dZdhc ba ^\mo j_`bfh\ dhgljhey mklZgh\e_g — dhgljhev q_lghklb (even parity beb dhgljhev g_q_lghklb (odd parity).

>himklbf i_j_^Z_lky [Zcl Hg kh^_j`bl q_luj_ l _ q_lgh_ dhebq_kl\h _^bgbp Ihwlhfm _keb \dexq_g j_`bf dhgljhey g_q_lghklb dhgljhevguc [bl mklZgZ\eb\Z_lky \ qlh[u h[s__ qbkeh _^bgbp klZeh g_q_lguf B gZh[hjhl dh]^Z mklZgh\e_g j_`bf dhgljhey q_lghklb dhgljhevguc [bl ijbjZ\gb\Z_lky qlh[u khojZgblv dhebq_kl\h _^bgbp q_lguf

BlZd \hl qlh ijhbkoh^bl k [Zclhf ^Zgguo ijb _]h ij_h[jZah- \Zgbb ba iZjZee_evghc \ ihke_^h\Zl_evgmx b ba kbgojhgghc \ Zkbgojhggmx nhjfm ih klZg^Zjlm9jbk

Ihke_ i_j_^Zqb gZijbf_j ih l_e_nhgghfm dZgZem 8$57 ijbgbfZxs_]h dhfivxl_jZ ij_h[jZam_l ^Zggu_ h[jZlgh \ h[uqguc 8-[blh\uc nhjfZl

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Wlb ljb iZjZf_ljZ fh`gh f_gylv ba dhffmgbdZpbhgghc ijh]jZffu JZamf__lky hgb ^he`gu kh\iZ^Zlv m ijb_fgbdZ b i_j_^ZlqbdZ bgZq_ ^Zggu_ [m^ml bkdZ`Zlvky QZklh agZq_gby wlbo iZjZf_ljh\ ibrml khdjZs_ggh gZijbf_j N hagZqZ_l © [blh\ ^Zgguo hlkmlkl\b_ None dhgljhey q_lghklb h^bg klh-ih\uc [blª QZs_ \k_]h bkihevamxlky bf_ggh wlb agZq_gby lZd qlh _keb \u g_ agZ_l_ dZdb_ iZjZf_lju mklZgh\e_gu gZ ^jm]hf dhgp_ ebgbb ihijh[mcl_1

V.I b ijhlhdheu dhjj_dpbb hrb[hd

KlZg^Zjl V h[_ki_qb\Z_l hq_gv keZ[mx aZsblm hl hrb[hd g_ba[_`gh \hagbdZxsbo ba-aZ ihf_o \ dZgZe_ k\yab Djhf_ lh]h wnn_dlb\ghklv i_j_^Zqb ijb wlhf ^h\hevgh gbadZ lZd dZd gZ dZ`^uc [Zcl ihe_aguo ^Zgguo ijboh^blky fbgbfmf ^\Z [blZ kem`_[ghc bgnhjfZpbb Ihwlhfm kh\j_f_ggu_ fh^_fu j_Zebamxl [he__ wnn_dlb\gu_ ijhlhdheu jZaf_j [ehdZ \ dhlhjuo [hevr_ Z Ze]hjblf \uqbke_gby dhgljhevghc kmffu agZqbl_evgh keh`g__ q_f ijZ\beZ mklZgh\db dhgljhevgh]h [blZ \9

LZd _keb \ fh^_f_ j_Zebah\Zg ZiiZjZlguc ijhlhdhe dhjj_dpbb hrb[hdgZijbf_j V.42) lh kbgojhggh-Zkbgojhggh_ ij_h[jZah\Zgb_ ih klZg^Zjlm 9klZgh\blky g_gm`guf Ihwlhfm fh^_f ihemqb\ hl dhfivxl_jZ ^Zggu_ kjZam `_ m[bjZ_l klZjlh\u_ klhih\u_ b dhgljhevgu_ [blu Ihke_ wlh]h [Zclu ^Zgguo kh[bjZxlky \ [he__ djmigu_ [ehdb b kgZ[`Zxlky dhgljhevghc kmffhc dZd ij_^mkfhlj_gh ijhlhdhehf9klj

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