More Modem Commands

The Hayes Command Set

Basic Command Set

A capital character followed by a digit. For example, M1.

Extended Command Set

An "&" (ampersand) and a capital character followed by a digit. This is an extension of the basic command set. For example, "&M1". Note that "M1" is different from "&M1".

Register Commands

Sr=n where "r" is the number of the register to be changed and "n" is the new value that is being assigned.

Here are some of the most important characters that may appear in the modem initialization string. These characters normally should not be changed.

AT

tells the modem that modem commands follow. This must begin each line of commands.

Z

resets the modem to default state

~ (tilde)

makes your software pause for half a second. You can use more than one ~ in a row. For example, "~~~~" tells the software to pause two seconds.

^M

sends the terminating Carriage Return character to the modem. This is a control code that most communication software translate as a "carriage return."

Ask your modem

AT$

HELP, Command Quick Reference (CTRL-S to Stop, CTRL-C to Cancel)

&$

HELP, Ampersand Commands

D$

HELP, Dial Commands

S$

HELP, S Registers

AT&$

HELP, Ampersand Commands

The Basic Hayes Command Set - Alphabetical

AT$

HELP, Command Quick Reference (CTRL-S to Stop, CTRL-C to Cancel)

&$

HELP, Ampersand Commands

A/

Repeat last executed command. Use primarily to re-dial, AT nor [Rtrn] required

AT

Required Command mode prefix (Attention Modem)

A

Answer Call

Bn

n=0 V32 Mode/CCITT ans Seq

n=1 Bell Answer Seq

n=2 Verbose/Quiet On Answer

Dn

Dial a Telephone Number

n=0..9#*TPR,;"W@!()-

DL

Dial Last Phone Number

DSn

Dial Stored Phone Number

D$

HELP, Dial Commands

En

n=0 No Command Echo

n=1 Echo Command Chars

Fn

n=0 Online Echo

n=1 No Online Echo

Hn

n=0 On Hook (Hang Up)

n=1 Off Hook

In

n=0 Product Code

n=1 Checksum

n=2 RAM Test

n=4 Current Settings

n=5 NVRAM Settings

n=6 Link Diagnostics

n=7 Product Configuration

Ln

n=0 Low Speaker Volume

n=1 Low Speaker Volume

n=2 Med Speaker Volume

n=3 Hi Speaker Volume

Mn

n=0 Speaker Off

n=1 Speaker OnUntil CD

n=2 Speaker Always On

n=3 Speaker Off During Dial

On

n=0 Return Online

n=1 Return Online & Retrain

P

Pulse Dial

Qn

n=0 Result Codes Sent

n=1 Quiet (No Result Codes)

Sr=n

Sets Register "r" to "n"

Sr?

Query Register "r"

S$

HELP, S Registers

T

Tone Dial

Vn

n=0 Numeric Responses

n=1 Verbal Responses

Xn

n=0 Basic Result Codes

n=1 Extended Result Codes

n=2-4 Advanced Result Codes

Yn

Select power on/reset default configuration

n=0 Next reset to &W0 settings

n=1 Next reset to &W1 settings

Zn

Reset modem based on current DIP switch settings

n=0 Dipswitch #7 determines reset

n=1 Reset to &W0 settings

n=2 Reset to &W1 settings

n=3 Reset to &F0 settings

n=4 Reset to &1 settings

n=5 Reset to &F2 settings

+++

Escape Code

The Extended Hayes Command Set (Ampersand Commands )

AT&$

HELP, Ampersand Commands

&An

n=0 Disable /ARQ Result Codes

n=1 Enable /ARQ Result Codes

n=2 Enable /Modulation Codes

n=3 Enable /Extra Result Codes

&Bn

n=0 Floating DTE Speed

n=1 Fixed DTE Speed

n=2 DTE Speed Fixed When ARQ

&Cn

n=0 CD Always On

n=1 Modem Controls CD

&Dn

n=0 Ignore DTR

n=1 On-Line Command Mode

n=2 DTE Controls DTR

&Fn

n=0 Load Factory 0, no FC

n=1 Load Factory 1, HW FC

n=2 Load Factory 2, SW FC

&Gn

n=0 No Guard Tone

n=1 550 Hz Guard Tone

n=2 1800 Hz Guard Tone

&Hn

n=0 Disable TX Flow Control

n=1 CTS

n=2 Xon/Xoff

n=3 CTS and Xon/Xoff

&In

n=0 Disable RX Flow Control

n=1 Xon/Xoff

n=2 Xon/Xoff Chars Filtered

n=3 HP Enq/Ack Host Mode

n=4 HP Enq/Ack Terminal Mode

n=5 Xon/Xoff for non-ARQ Mode

&Kn

n=0 Disable Data Compression

n=1 Auto Data Compression

n=2 Enable Data Compression

n=3 Selective Data Compression

&Mn

n=0 Normal Mode

n=4 ARQ/Normal Mode

n=5 ARQ Mode

&Nn

n=0 Highest Link Speed

n=1 300 bps

n=2 1200 bps

n=3 2400 bps

n=4 4800 bps

n=5 7200 bps

n=6 9600 bps

n=7 12000 bps

n=8 14400 bps

&Pn

n=0 N.American Pulse Dial

n=1 UK Pulse Dial

&Rn

n=1 Ignore RTS

n=2 RX to DTE/RTS high

&Sn

n=0 DSR Always On

n=1 Modem Controls DSR

&Tn

n=0 End Test

n=1 Analog Loopback (ALB)

n=3 Digital Loopback (DLB)

n=4 Grant Remote DLB

n=5 Deny Remote DLB

n=6 Remote Digital Loopback

n=7 Remote DLBWith Self Test

n=8 ALB With Self Test

&Wn

n=0 Store Configuration 0

n=1 Store Configuration 1

&Yn

n=0 Destructive

n=1 Destructive/Expedited

n=2 Nondest./Expedited

n=3 Nondest./Unexpedited

&Zn=s

Store Phone Number

&Zn?

Query Phone Number

Do You Know Something We Should Know?

The Chebucto
Neighbourhood
Websites of Dozens of Groups, Organizations and Businesses hosted by Chebucto

By Alphabet      By Subject

Chebucto Photo Gallery