Notice: Hayes Microcomputer Products, Inc. reserves the right to make
improvements to the product described in this manual at any time and
without notice.

Hayes, the Hayes icon, the Hayes logo, the Hayes '302 Escape Sequence
Patent icon, V-series, Smartmodem, Smartcom, OPTIMA and ACCURA are
trademarks of Hayes Microcomputer Products, Inc. V.FC is a trademarks of
Rockwell International Corporation. MNP is a trademark of Microcom, Inc.
Other trademarks mentioned in this document are trademarks of their
respective companies.





This document is copyrighted. All rights are reserved. This document may
not, in whole or part, be copied, photocopied, reproduced, translated or
reduced to any electronic medium or machine-readable form without prior
consent, in writing, from Hayes Microcomputer Products, Inc.

Copyright 1993 Hayes Microcomputer Products, Inc.
All rights reserved. Printed in U.S.A.



Note: This version of the "Hayes AT Command Reference for OPTIMA and
ACCURA Products" is a special version edited for bulletin-board
downloading. As a plain ASCII character file, it therefore does not
contain the graphic elements provided in the printed version.


The following graphic characters are used to denote the start of
Chapters, 1st Level Headings, 2nd Level Headings, and Table Headings:

Chapter Headings are preceded by:
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1st Level Headings are preceded by:
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Table of Contents


Chapter 1: Introduction

Scope
Organization of This Document
Conventions
Hex Notation


Chapter 2: Basic Command Interface

Overview
Modes
DTE Interface Speeds
AT Speed
Autobaud	
Line Speed
Connect Speed
Response Speed
Character Formats
General
Stop Bits
Length And Parity
Command Processing
Overview
Command Process
AT Entry
Command Entry And Editing
Command Delineation
A/ The Repeat Command
Command Execution
Command Validity
Information Text
Result Codes
Execution Time
Assumed Zero Suffixes
Out-of-Range Suffixes


Chapter 3: Extended Command Syntax

General
Action Commands
Command Syntax
Test Command
Invalid Syntax
Parameter Commands
Write Parameter Value
Read Parameter Value
Test Parameter
Parameter Values
Command Termination
Strings
Compound Value Strings
Allowed Characters
Spaces
Special Value Formats


Chapter 4: AT Commands

General
A - Answer Command
Bn - Communications Options
D - Dial Command
En - Select Command Character Echo Option
Hn - Control The Switchhook
I0 - Identify The Product Code
I2 - Perform ROM Checksum Test
I7 - Version Number
Ln - Select Speaker Volume Level
Mn - Select Speaker Function Option
Nn - Select Negotiate Handshake Option
On - Go Online Command
P - Select Pulse Dialing Method
Qn - Select Result Code Option
Sn= - Write To An S-Register
Sn? - Read An S-Register
T - Select Tone Dialing Method
Vn - Select Response Format Option
Wn Select Extended Result Code
Xn Select Call Progress Option
Yn Select Long Space Disconnect Option
Zn Perform Soft Reset
&An - Select Originate/Answer Role For Autoanswer
&Cn - Select Data Carrier Detect Option
&Dn Select Data Terminal Ready Option
Dumb, switched
Smart AT, switched
Timing of DTR Off-To-On Transitions
Timing of DTR On-To-Off Transitions
DTR-Initiated Hard Reset (&D3 in effect)
&F - Load Factory Default Profile
&Gn - Select Guard Tone Option
&Kn - Select Flow Control Option
Transparent flow control
&Pn - Select Pulse Dialing Parameters
&Qn - Select Communications Mode Option
&Rn - Select RTS/CTS Option
&Sn - Select Data Set Ready Option
&T0 - Terminate Test In Process
&T1 - Initiate Local Analog Loopback
&T3 - Perform Local Digital Loopback
&T4 - Enable Granting Of RDL Requests
&T5 - Deny Granting Of RDL Requests
&T6 - Initiate Remote Digital Loopback
&T7 - Initiate RDL With Self Test
&T8 - Local Loopback With Self Test
&T19 - Perform RTS/CTS Cable Test
&Un - Disable Trellis Coding
&V - View Configuration Profiles
&Wn - Store Active Profile
&Xn - Select Sync Transmit Clock Source
&Yn - Select Stored Profile For Hard Reset
&Zn= - Store Telephone Number
, <comma> Perform Pause
= - Write To An S-Register
? - Read An S-Register
P - Select Pulse Dialing
T - Tone


Chapter 5: Result Codes

Basic Result Codes
Extended Result Codes


Chapter 6: S-Registers

Introduction
Scope
Command Lines
Default Value
Types
Behavior Of Unimplemented S-registers
Classifications Of S-registers
Value Evaluation Rules
Summary Of S-register Behaviors
S0 - Ring After Which To Answer
S1 - Ring Count
S2 - Hayes Escape Character
S3 - Carriage Return Character
S4 - Line Feed Character
S5 - Backspace Character
S6 - Wait Before Blind Dialing
S7 - Wait For Carrier
S8 - Pause Time For Comma
S9 - Carrier Recovery Time
S10 - Lost Carrier Hang Up Delay
S11 - DTMF Dialing Speed
S12 Hayes Escape Guard Time
S16 - Test in Progress
S18 - Modem Test Timer
S19 - AutoSync Options
S25 - Detect DTR Change
S26 - RTS To CTS Delay Interval
S30 - Inactivity Timeout
S31 - XON Character
S32 - XOFF Character
S36 - Negotiation Failure Treatment
S37 - Desired DCE Line Speed
S38 - Hang-up Timeout
S43 - Current Line Speed
S44 - Framing Technique
S46 - Protocol/Compression Selection
S48 - Feature Negotiation Action
S49 - Buffer Low Limit
S50 - Buffer High Limit
S70 - Maximum Number of Retransmissions
S73 - No Activity Timeout
S82 - Break Selection
S86 - Connection Failure Cause Code
S91 - Select Dial-up Line Transmit Level
S95 - Extended Result Code Bit Map
S97 - V.32 Late Connecting Handshake Timing
S105 - Frame Size
S108 - Signal Quality Selector
S109 - Carrier Speed Selector
S110 - V.32/V.32 bis Selector
S113 - Calling Tone Control
S121 - Use of DTR
S141 - Detection Phase Timer
S142 - Online Character Format
S144 - Autobaud Speed Group Selection


Chapter 7: Modem States

Modem Functions
Major States


Chapter 8: Processes and Procedures

Answering Process
Carrier Detection
Dialing Process
Hayes Improved Escape Sequence with Guard Time
Handshaking Process
Hang-up Process
Resets
Power On Reset
Hard Reset
Soft Reset
Key Press Abort
Online State
Online Command State
Response To Ringing
General
RI Lead.
S1 Register.
RING Result Code.
RDL Process


Chapter 9: FAX Functions

Introduction
Philosophy
Modem FAX Modes
FAX Class 1 Mode
DTE Interface Leads
General FAX Operation
FAX Commands and Responses
FAX Identification Responses
FAX Commands in Data Mode
Escape From On-line State
DTE Interface Speed
FAX Class 1
General
Commands
Answer Handshake
+FAE Automatic Data/FAX Handshake
Result Codes
Flow Control
Data Commands and Re