AT&T System 85 - page 560

MDC 9000 Cordless Telephone

Additional Documents

The following documents contains additional information relating to the MDC 9000 Cordless Tele-

phone: (Use the 9 digit number listed after each document to order that book from the AT&T

GBCS Publications Fulfillment Center.)

DEFINITY Generic 1, 2, and 3, System 75 and System 85 MDC 9000 Cordless Tele-

phone User’s Guide

, 555-230-769

MDC 9000 Cordless Business Telephone Installation Manual

, 503-801-101.

3-470

Contents

Main Page Contents 7102A and 7102 Plus Voice Terminals 7103A Fixed Feature Voice Terminal 7103A Programmable Voice Terminal 7104A Voice Terminal 7203H Voice Terminal 7205H Voice Terminal 7303S Voice Terminal 7305S Voice Terminal 7401D and 7401 Plus Voice Terminals 7402 Plus Voice Terminal 7403D Voice Terminal 7404D Voice Terminal 7405D Voice Terminal 7406D, 7406BIS, and 7406 Plus Voice Terminals 7407D, Enhanced 7407D, and 7407 Plus Voice Terminals 7410D and 7410 Plus Voice Terminals 7434D Voice Terminal 7444 Voice Terminal 8403 Voice Terminal 8410 Voice Terminal 8434 and 8434DX Voice Terminal CALLMASTER and CALLMASTER II and III Voice Terminals 500 Series Telephone 2500 Series Telephones 2500 DMGC Telephone 2500 YMGK Telephone 2500 MMGL and 2500 YMGL Telephones 8101 Telephone 8102 and 8102M Telephones 8110 and 8110M Telephones ISDN 7505 Modular Terminal ISDN 7506 Display Terminal ISDN 7507 Display Terminal ISDN 8503T Voice Terminal ISDN 8510T Voice/Data Terminal ISDN 8520T Voice/Data Terminal ISDN 8528T Voice Terminal MDC 9000 Cordless Telephone MDW 9000 Wireless Telephone Other Voice Terminals ADJUNCTS Call Coverage Modules Digital Display Module Function Key Modules 801A Expansion Module Headset Adapters Message Waiting Indicator 4A, S101A, and S102A Speakerphones S201A and S202A Speakerphones S203A Speakerphone Loudspeaker Messaging Cartridge Automatic Dialer DATA MODULES 7400A Data Module 7400B and 7400B Plus Data Module 8400B Plus Data Module 7500B Data Module ISDN Asynchronous Data Module (ADM) Digital Terminal Data Module (DTDM) Z702AL1 Data Service Unit (DSU) 703A Data Service Unit (DSU) DEFINITY High Speed Link Processor Data Module (PDM) Trunk Data Module (TDM) Modular Trunk Data Module (MTDM) 3270 Data Module Asynchronous Data Unit (ADU) DCIU Interface Units 2500-Series Data Service Unit (DSU) PC PLATFORMS (PC/PBX AND PC/ISDN) AND APPLICATION SOFTWARE PC Platforms (PC/PBX and PC/ISDN) Page Figures Page Page Page Page Tables Page INTRODUCTION Purpose Page Organization Page Page Page GENERAL INFORMATION Voice Terminals single-line voice terminals multi- appearance voice terminals. Single-Line Voice Terminals Multi-Appearance Voice Terminals Page Facilities Common to All Voice Terminals Administrable Buttons must Page Page Red Light Green Status Light Tones External Ringing Tones outside the voice terminal Handset Tones Desk/Wall Mounting Arrangements Page Page Page Data Modules Page Page Data Terminals Technical Specifications Call Progress Tones External Ringing Tones Indicator Lights Signals EXPOSED PORT PROTECTION Requirements AT&T System 85 Electrical Protection, Grounding, and Exposure Checklist AT&T System 75 Electrical Protection, Grounding, and Exposure Checklist Exposed Ports And Terminals Defined Page DEFINITY Communications System Generic 1 and Generic 3 Wiring DEFINITY Communications System Generic 2 and System 85 Wiring Page AVAILABILITY Page Page Page Page Page ADJUNCT POWER Page Page Page The MSP-1 Power Supply Contents of the MSP-1 Package (and Comcodes) Connecting the Power Supply ADJUNCT POWER 2-37 ADJUNCT POWER FIGURE 2-6. Local Powering Arrangement for Adjuncts Connected to the 8102 Analog Telephone ADMINISTRATION Aliasing Page Page Page Page Page Page Page Page Page Button and Feature Caveats System 75 and DEFINITY G1 System 85 and DEFINITY G2 PC/ISDN Installation and Reference Manual 6 None personal computer VOICE TERMINAL FEATURES Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page 7101A Voice Terminal Page Page Page Page Page Page Page 7102A and 7102 Plus Voice Terminals Page Page DEFIN- ITY Communications System Generic 1 and Generic 3 Wiring Guide Page Page Page Page 7103A Fixed Feature Voice Terminal Page Page Page 7103A (Fixed Feature) Equipment Price Element Code (PECs) Page Page Page 7103A Programmable Voice Terminal Page Page Page Page Page Page Page 7104A Voice Terminal Eight Special Fixed Feature Buttons Eight dual function buttons Loudspeaker Display Page Page Page Page Page Page 7203H Voice Terminal Page Page Page 7203H Equipment Price Element Code (PECs) System 85 7203H Voice Terminal Users Guide Page Page Page 7205H Voice Terminal Page Page Page Page Page Page Page 7303S Voice Terminal Page Page Page Page Page Page Page 7305S Voice Terminal Page Page Page Page Page Page 7305S Voice Terminal 7401D and 7401 Plus VOICE TERMINAL 3-88 FIGURE 3-9. The 7401 Plus (7401D02A) Voice Terminal Page Page 7401D and 7401 Plus Voice Terminals The Feature Button Page Page Page Page Page Buttons 1 and 2 are line appearances. Buttons 3 9 are F1 F7. 3-98 3-99 7401D Equipment PECs & COMCODES 7401 Plus Equipment with PECs and COMCODES Page Page Page 7402 Plus VOICE TERMINAL FIGURE 3-12. The 7402 Plus Voice Terminal 3-105 Page 7402 Plus Voice Terminal Page Page Page Page Page 7402 Plus Voice Terminal * 123 456 789 # O FIGURE 3-13. Button Numbering for Administering the 7402 Plus Voice Terminal * O# Page Page Page Page Page Page 7403D Voice Terminal Page Page Page Page Page Page Page 7404D Voice Terminal Page Page Page Page Page Page Page 7405D Voice Terminal Page Page Page 7405D Equipment Price Element Code (PECs) Page Page 7406D, 7406BIS, and 7406 Plus VOICE TERMINALS FIGURE 3-18. The 7406D (7406D01A or 7406D03A) Voice Terminal with Display 3-144 FIGURE 3-19. The 7406BIS (7406D05A) Voice Terminal with Display 3-145 FIGURE 3-20. The 7406 Plus (7406D07A) Voice Terminal with Display 3-146 7406D, 7406BIS, and 7406 Plus Voice Terminals Page Page SELECT button (on 7406 Plus only) One-level Feature-only and Two-level Feature-only Buttons Speakerphone (on 7406BIS and 7406 Plus) must cannot only Loudspeaker/Spokesman/Speaker Feature MUTE button (on 7406BIS and 7406 Plus) VOLUME button (on 7406BIS and 7406 Plus) Self-Test Page Page Page Page Page ABC DEF MNOJKLGHI PRS TUV WXY Select Ring 3-158 Speaker FIGURE 3-21. Button Numbering for Administering the 7406D and 7406BIS Voice Terminals ABC DEF MNOJKLGHI PRS TUV WXY Select Ring 3-159 Speaker FIGURE 3-22. Button Numbering for Administering the 7406D and 7406BIS Voice Terminals 123 456 789 # * O FIGURE 3-23. Button Numbering for Administering the 7406 Plus Voice Terminal ABC DEF MNOJKLGHI PQRS TUV WXYZ Oper FIGURE 3-24. Button Numbering for Administering the 7406 Plus Voice Terminal 7406D/7406BIS Equipment PECs & COMCODES Page Page 7406 Plus Equipment PECs and COMCODES 7406 Voice Terminal Installation Instructions System 75 7406D Voice Terminal Users Guide DEFINITY Communications System Generic 1 7406D Voice Terminal Users Guide Page Page 7407D, Enhanced 7407D, and 7407 Plus VOICE TERMINALS FIGURE 3-25. The 7407D (7407D01B) Voice Terminal 3-169 FIGURE 3-26. The Enhanced 7407D (7407D02C) Voice Terminal 3-170 FIGURE 3-27. The 7407 Plus (7407D02D) Voice Terminal 3-171 Page 7407D, Enhanced 7407D, and 7407 Plus Voice Terminals Switch Options for the 7407D and Enhanced 7407D DIP Switch Options for the 7407 Plus Page Four Standard Fixed Feature Buttons CALCULATOR/SELECT RING button (on 7407D only) SELECT RING button (on Enhanced 7407D only) SELECT button (on the 7407 Plus only) Feature-only Buttons on the 7407D (7407D01B) Feature-only Buttons on the Enhanced 7407D (7407D02C) Feature-only Buttons on the 7407 Plus (7407D02D) 7407 Plus or cannot MICROPHONE button (on 7407D only) MUTE button (on the Enhanced 7407D and 7407 Plus) VOLUME control button (on Enhanced 7407D and 7407 Plus) Self-Test (on Enhanced 7407 and 7407 Plus) Page Page Page cannot can be DEFINITY Communications System Generic 3 Implemen- Display FIGURE 3-28. Button Numbering for Administering the 7407D (7407D01B) Voice Terminal 3-186 123 456 789 # Assignments 13 and 14 * Conference Drop 3-187 Transfer Hold Display FIGURE 3-30. Button Numbering for Administering the Enhanced 7407D (7407D02C) Voice Terminal 3-188 Message Speaker Mute Select Ring 123 456 789 * Conference Drop 3-189 Transfer Hold Button Assignments 3 - 12 FIGURE 3-32. Button Numbering for Administering the 7407 Plus Voice Terminal 3-190 123 456 789 # Reset/Spkr * Button Assignments 3 - 12 3-191 Test FIGURE 3-33. Button Numbering for Administering the 7407 Plus Voice Terminal Page 7407 Plus Equipment PECs and COMCODES Page Page Page 7410D and 7410 Plus VOICE TERMINALS FIGURE 3-34. The 7410D (7410D01A) Voice Terminal 3-197 FIGURE 3-35. The 7410 Plus (7410D02A) Voice Terminal 3-198 7410D and 7410 Plus Voice Terminals Page Page Page Page Page FIGURE 3-36. Button Numbering for Administering the 7410D Voice Terminal 3-205 FIGURE 3-37. Button Numbering for Administering the 7410D Voice Terminal 3-206 123 456 789 * O# FIGURE 3-38. Button Numbering for Administering the 7410 Plus Voice Terminal 123 456 789 ABC DEF MNOJKLGHI PQRS TUV WXYZ * FIGURE 3-39. Button Numbering for Administering the 7410 Plus Voice Terminal 7410D Equipment with PECs and COMCODES 7410 Plus Equipment PECs and COMCODES Page Page Page Page 7434D Voice Terminal Standard Fixed Feature Buttons Administrable Buttons Page Page Page Page 7434D Voice Terminal 7444D VOICE TERMINAL 3-221 FIGURE 3-41. The 7444 Voice Terminal Page 7444 Voice Terminal Four Standard Fixed Feature Buttons SELECT button Seven Display Feature Buttons (with a green status light) Page Page Page Page Page and DEFINITY Communications System Generic 1 Implemen- Volume 123 456 789 Speaker * O Conference Drop Transfer Hold Select Mute * O Conference Drop Transfer Hold Select Mute Page Page Page Page 8403 VOICE TERMINAL * 3-237 FIGURE 3-44. The 8403 Voice Terminal Page 8403 Voice Terminal Page Page Page Page Page Page Page Page FIGURE 3-45. Button Numbering for Administering the 8403 Voice Terminal 3-248 FIGURE 3-46. Button Numbering for Administering the 8403 Voice Terminal 3-249 8403 Equipment PECs & COMCODES Page Page 8410 VOICE TERMINAL * 3-253 FIGURE 3-47. 8410D Voice Terminal (With Display) Page 8410 Voice Terminal in addition to The SHIFT Button Speakerphone must Page Page BLANK Page Page Page Page Page Page DEFINITY Communications System Generic 3 Implemen- FIGURE 3-48. Button Numbering for Administering the 8410 Voice Terminal 3-268 FIGURE 3-49. Button Numbering for Administering the 8410 Voice Terminal 3-269 8410 Equipment PECs & COMCODES Page Page Page 8434 and 8434DX VOICE TERMINAL * 3-274 FIGURE 3-50. 8434 Voice Terminal * FIGURE 3-51. 8434DX Voice Terminal 3-275 Page 8434 and 8434DX Voice Terminal in addi- tion to Page The SHIFT button Page TEST button Page Page BLANK Page Page Page Page Page Page FIGURE 3-52. Button Numbering for Administering the 8434 and 8434DX Voice Terminal FIGURE 3-53. Button Numbering for Administering the 8434 and 8434DX Voice Terminal 8434 and 8434DX Equipment PECs and COMCODES Page Page Page Page CALLMASTERAND CALLMASTERII & III VOICE TERMINALS FIGURE 3-54. The 602 CALLMASTER Voice Terminal with Optional Handset 3-298 FIGURE 3-2. The CALLMASTER II and CALLMASTER III Voice Terminal 3-299 Page CALLMASTERand CALLMASTERII and III Voice Terminals The Recorder Interface Be aware that this tone may be a legal requirement. Feature-Only Buttons SELECT button Page Page Button Numbering * 3-308 Feature Button Assignments 1 18 Button Assignments 1 10 FIGURE 3-3. Button Numbering for Administering the 602 CALLMASTER Voice Terminal * FIGURE 3-4. Button Numbering for Administering the 602 CALLMASTER Voice Terminal 3-309 * Button 3-310 1 6 Feature Button 1 18 * Button 3-311 3 8 Feature Button 13 30 CALLMASTER Equipment Price Element Code (PECs) Page Page Page Page 500 Series Telephone Physical Features Page Page Page Page Page 2500 Series Telephones RECALL button Page Page Price Element Code (PECs) Page Page 2500 DMGC Telephone RECALL button Message light Page Page Page Page Page 2500 YMGK Telephone RECALL button Page Page 2500 YMGK Equipment Price Element Code (PECs) DEFINITY Generic 1 2500 YMGK Users Guide DEFINITY Generic 2 and System 85 2500 YMGK Users Guide System 75 2500 YMGK Users Guide 2500 MMGL and 2500 YMGL TELEPHONES 2500 YMGK Telephone FIGURE 3-11. The 2500 YMGL Telephone 3-340 2500 MMGL and 2500 YMGL Telephones Features on the 2500 YMGL Page Other Physical Features (on Both 2500 Telephones) Page Page Page 2500 MMGL and 2500 YMGL Telephones 8101 TELEPHONE 3-347 FIGURE 3-12. The 8101 Telephone Page 8101 Telephone Designation Card Positive Disconnect Page Page Page System 75, System 85, DEFINITY Communications System Generic 1 and 3 and 2 8101, 8102, and 8110 Telephones Instructions for Installation and Switch Information 8101 Telephone 8102 AND 8102M TELEPHONES 3-355 # * FIGURE 3-13. The 8102 and 8102M Telephone (The 8102M is shown here) Page 8102 and 8102M Telephones Programmable Dialing Buttons PROGRAM and PAUSE buttons Page Page Page Page 8102 and 8102M Telephones PECs and COMCODES Page Page Page 8102 and 8102M Telephones 8110 and 8110M TELEPHONES 3-367 FIGURE 3-14. The 8110 and 8110M Telephones (The 8110M is shown here) Page 8110 and 8110M Telephones Page Page Page Page Page not Administration of Hidden Features 8102M and 8110M Telephones Quick Reference Guide to be done ONLY by the sys- tem administrator Ringer Equivalency Numbers 8110 and 8110M Telephones Equipment PECs and COMCODES Page Page 8110 and 8110M Telephones ISDN 7505 MODULAR TERMINAL 3-379 # 123 456 789 * Page ISDN 7505 Modular Terminal Page Page Page Page Page ISDN 7505 Modular Terminal ISDN 7506 DISPLAY TERMINAL 3-387 FIGURE 3-16. The 7506 Asynchronous Data Modular Display Terminal Page ISDN 7506 Display Terminal Page Page Page Page 7506 Equipment Price Element Code (PECs) ISDN 7506 Display Terminal ISDN 7507 DISPLAY TERMINAL 3-395 # 123 456 789 * Page ISDN 7507 Display Terminal Page Page Page Page 7507 Equipment Price Element Code (PECs) ISDN 7507 Display Terminal ISDN 8503T VOICE TERMINAL 3-403 FIGURE 3-18. The Desk-mounted ISDN 8503T Voice Terminal Page ISDN 8503T Voice Terminal Four Standard Fixed Features either Twelve Programmed Memory Locations PROGRAM button Page Jacks Page Phantom or Auxiliary Power only Terminating Resistors Page 8503T Equipment PECs and COMCODES Page Page ISDN 8503T Voice Terminal ISDN 8510T VOICE/DATA TERMINAL 3-415 FIGURE 3-19. The ISDN 8510T Voice/Data Terminal Page ISDN 8510T Voice/Data Terminal Page or EXIT button Page Page Page Page Data Features ISDN 8500 Series Display Terminal ADM Users Manual Phantom or Auxiliary Power only Terminating Resistors only not Button Numbering Page 8510T Equipment PECs and COMCODES Page ISDN 8510T Voice/Data Terminal ISDN 8520T VOICE/DATA TERMINAL 3-431 FIGURE 3-20. The ISDN 8520T Voice/Data Terminal Page ISDN 8520T Voice/Data Terminal Nine Fixed Features either or REDIAL button or EXIT button Page Page Color Data Features ISDN 8500 Series Display Terminal ADM Users Manual Auxiliary Power Supply Terminating Resistor Button Numbering Page Page Page Page ISDN 8520T Voice/Data Terminal ISDN 8528T VOICE TERMINAL 3-445 * FIGURE 3-21. The ISDN 8528T Voice Terminal Page ISDN 8528T Voice Terminal Nine Fixed Features Page Page Page Page Page Page 8528T Equipment PECs and COMCODES Page Page Page ISDN 8528T Voice Terminal MDC 9000 CORDLESS TELEPHONE 3-458 * FIGURE 3-22. MDC 9000 Telephone, Top View of Handset, including Enlarged Display Area ISDN 8528T Voice Terminal FIGURE 3-23. MDC 9000 Telephone, Top View of Charging Base 3-459 Page MDC 9000 Cordless Telephone Handset Features Outside Line or Intercom/ Programmable Feature Buttons STAT Button (Handset) ON/OFF Button Page Charging Base Features Display Information or or Out-of-Range Indication Distance and Installation Limitations (for the Charging Base) Page Page FCC Part 15 Rules MDC 9000 Equipment PECs & COMCODES Page Page MDW 9000 WIRELESS TELEPHONE * 3-472 FIGURE 3-26. MDW 9000 Telephone including Enlarged Display Area FIGURE 3-27. MDW 9000 Telephone, Top View of Charging Cradle 3-473 FIGURE 3-28. MDW 9000 Telephone, Radio Module 3-474 MDW 9000 Wireless Telephone Handset Features Page Charging Cradle Features Radio Module Features Display Information or or not Out-of-Range Indication Distance and Installation Limitations Page FCC Part 15 Rules MDW 9000 Equipment PECs & COMCODES Page Page Other Voice Terminals Voice Terminals Reusable from Other Systems Advantages of Reusable Terminals Disadvantages of Reusable Terminals Models 7302H, 7303H, 7305H01B, and 7305H02B Multi-Button Electronic Telephone (MET) Sets Page Page ADJUNCTS Page Page Page Call Coverage Modules Mounting Page Page Page Digital Display Module Automatic Displays Auxiliary Displays On/Off Switch Assignable Function Buttons Display Functions Digital Display Module PEC Codes Page Page Page Function Key Modules Feature buttons Page Page 801A EXPANSION MODULE 801A Expansion Module Mounting Administering the Expansion Module 801A 801A Expansion Module PEC Codes 801A Expansion Module Instruction Manual Page Page Page Headset Adapters On/Quiet Switch Off Switch Headset jack Headset Light Page Headset PEC Codes Page Page Page Message Waiting Indicator Light Page Page Page 4A, S101A, and S102A Speakerphones S101A and S102A Speakerphones On/Off button Sliding volume control Cord 4A Speakerphone Speakerphone PEC Codes Page 4A, S101A, and S102A Speakerphones S201A AND S202A SPEAKERPHONES 4-39 FIGURE 4-6. The S201A and S202A Speakerphones Page S201A and S202A Speakerphones Speakerphone button Volume control Reset button Cord S201A and S202A Speakerphone PEC Codes Page S201A and S202A Speakerphones S203A SPEAKERPHONE 4-44 FIGURE 4-7. The S203 Speakerphone S203A Speakerphone Speakerphone with light Page Page Page Page Page Loudspeaker Volume control ON/OFF switch Page Page Page Messaging Cartridge Messaging Cartridge Price Element Codes (PECs) Page Page Page Automatic Dialer Programmable buttons Four Fixed function buttons Page DATA MODULES Page DATA MODULES 7400A DATA MODULE 5-3 NEXT/NO BACK ENTER/YES HOME 7400A Data Module Page 7400A Data Module POWER/TEST light DATA light Page Page 7400A Data Module Price Element Codes (PEC) Page 7400B and 7400B Plus DATA MODULE 7400B and 7400B Plus Data Module except Page Tests Setting Options without with Notes for Use with PC Packages 7400B Data Module PEC Codes Page Page 8400B Plus Data Module 8400B Plus Data Module 8400B Plus Data Module 5-20 8400B Plus Data Module Page Page Tests AT S7 ATDP Setting Options Smm=nnn Smm? &V AT Notes for Use with PC Packages can alternate voice/data dialing only 8400B Plus Data Module PEC Codes AT&T 8400B Plus Data Module Users Guide Page Page 7500B Data Module POWER/TEST Light DATA Light Page Asynchronous DCE Features Synchronous DCE Features Page ISDN Asynchronous Data Module (ADM) Page Page Page Digital Terminal Data Module (DTDM) Speed Indicator lights Speed selector switch Test switch Option switches Data Call Switch DTDM Equipment PEC Codes Page Page Page Z702AL1 Data Service Unit (DSU) Page Z702AL1 DSU PEC Codes Page Page Page 703A Data Service Unit (DSU) Physical Appearance 703 DSU Price Element Codes (PECs) Addtional Documents Page 703A Data Service Unit (DSU) DEFINITYHigh Speed Link 5-53 NEXT/NO BACK ENTER/YES HOME DEFINITY High Speed Link Page DEFINITY High Speed Link POWER/TEST light DATA light Page Administration Switched Requirements Permanent (Private Line) Requirements Releases for Permanent Applications DEFINITY High Speed Link Users Manual Permanent Endpoints Permanent Applications Page Hight Speed Link Price Element Codes (PEC) DEFINITY High Speed Link Users Manual Page Page Page Processor Data Module (PDM) PDM Equipment Price Element Code (PEC) Processor Data Module Users Guide Page Page Trunk Data Module (TDM) TDM Equipment Price Element Codes (PEC) Trunk Data Module Users Guide Page Trunk Data Module (TDM) MODULAR TRUNK DATA MODULE (MTDM) 5-72 MTDM FIGURE 5-6. The MTDM, the Stand-alone model Modular Trunk Data Module (MTDM) Functional elements Page MTDM Equipment Price Element Codes (PECs) Page Page Page 3270 Data Module Page The 3270A and 3270T The 3270C Cords Power 3270 Equipment Price Element Codes (PECs) 3270 Data Module User Manual Page Page Page Asynchronous Data Unit (ADU) Switch Z3A Data Module Price Element Codes (PECs) Page Page DCIU Interface Units 105A Isolating Data Interface (IDI) 48250 Local Distribution Service Unit 2500-Series DSU Page 2500-Series Data Service Unit (DSU) 2500-Series DSU Price Element Codes (PECs) 2500-Series Data Service Unit Users Manual Page Page PC Platforms (PC/PBX and PC/ISDN) Overview Platforms PC/PBX and PC/PBX MicroChannel Platforms Applications Capabilities PC/PBX Price Element Code (PEC) PC/ISDN Platform Applications Capabilities PC/ISDN Price Element Codes (PEC) PC/ISDN Platform Installation and Reference PC/ISDN Interface Software Developers Guide PC/PBX Platform Installation and Reference PC/PBX Connection Capabilities Page E78 Plus/ISDN Software Capabilities E78 Price Element Codes (PECs) Blank Templates for Model Design Page Index A B C D E F H I