3COM CORPORATION

DIRECT 2400

Card Type

Modem (asynchronous)

Chip Set

U.S.Robotics

Maximum Data Rate

2400bps

Data Bus

External

Data Modulation Protocol

Unidentified

CONNECTIONS

Function

Label

Function

Label

Line out/in - Unidentified

CN1

DC power - Unidentified

CN4

Line in/out - Unidentified

CN2

Power switch - Unidentified

SW1

RS-232/422 - Unidentified

CN3

   

USER CONFIGURABLE SETTINGS

Setting

Label

Position

í DTR normal

SW1/1

On

DTR Forced high

SW1/1

Off

í Verbose result codes

SW1/2

Off

Numeric result codes

SW1/2

On

í Result codes enabled

SW1/3

On

Result codes disabled

SW1/3

Off

í Commands displayed

SW1/4

Off

Commands not displayed

SW1/4

On

í Auto-answer mode enabled

SW1/5

Off

Auto-answer mode disabled

SW1/5

On

í CD signal forced high

SW1/6

On

CD signal normal

SW1/6

Off

í RJ-11 jack

SW1/7

Off

RJ-12, RJ-13 jack

SW1/7

On

í Smart mode

SW1/8

On

Dumb mode

SW1/8

Off

DIAGNOSTIC LED(S)

LED

Color

Status

Condition

Left

Green

On

Modem is in data mode

Left

Green

Off

Modem is not data mode

Left

Red

On

Modem is in analog loopback test mode

Left

Red

Blinking

Power on/self-test in progress

Right

Green

On

Carrier signal detected/ready to send data

Right

Green

Off

Carrier signal not detected/not ready to send data

Right

Red

Off

Modem is not receiving data/not displaying result codes

Right

Red

Blinking

Modem is receiving data/display result codes

Proprietary AT Command Set

ABORT

Type:

Immediate

Format:

Any key

Description:

Aborts answering/originating a call; modem hangs up.

ANSWER

Type:

Immediate

Format:

AT [cmds] A

Description:

Enables manual answer mode, the modem goes off-hook; pressing any key will abort.

ANSWER SEQUENCE

Type:

Configuration

Format:

AT [cmds] Bn [cmds]

Description:

Selects the answer sequence the modem will use

Command

Function

í B0

ITU-T answer sequence enabled

B1

Bell answer sequence enabled

ATTENTION

Type:

Immediate

Format:

AT [cmds]

Description:

Tells the modem that a command follows or use alone to test OK result code

CLOCK

Type:

Configuration

Format:

AT [cmds] Kn [cmds]

Description:

Displays connection duration or real time

Command

Function

í K0

Connection duration displayed in ATI3

K1

Real time displayed in ATI3. To set clock (military time) use ATI3=HH:MM:SSK1.

DIAL

Type:

Immediate

Format:

AT [cmds] D<#> [cmds]

Example:

ATDT 443-3388,,,1111;

Description:

Dials telephone number according to any modifiers included in the string

Note:

Any combination of modifiers can be used to produce the desired dial functions in sequence.

Command

Function

í P

Pulse dialing enabled

T

Tone dialing enabled

,

Dialing paused for 2 seconds

;

Modem returned to command state after dialing. Can only be placed at the end of the dial command.

"

Dials letters as if they were numbers; ATDT"GOMICRO"

!

Flash function initiated

@

Dial, wait for quiet answer, then continue to execute the rest of the dial string

W

Dial, wait for second dial tone, then continue to execute the rest of the dial string

R

Answer mode enabled; originate mode disabled following handshake initiation.

ECHO

Type:

Configuration

Format:

AT [cmds] En [cmds]

Description:

Controls echo function; display keyboard commands when enabled.

Command

Function

E0

Echo function disabled

E1

Echo function enabled

ECHO - ON-LINE

Type:

Configuration

Format:

AT [cmds] Fn [cmds]

Description:

Selects whether data sent while in data mode are echoed

Command

Function

F0

Local echo enabled

í F1

Local echo disabled

ESCAPE SEQUENCE

Type:

Immediate

Format:

+++AT [cmds] <CR>

Description:

Initiates the escape sequence and returns the modem to the on-line command state if it receives three escape characters set in S2 within the time allotted by S12.

Note: Do not precede this command with AT.

GUARD TONE

Type:

Configuration

Format:

AT [cmds] &Gn [cmds]

Description:

Commands the modem to transmit a guard tone

Note: Used primarily for international data transmission

Command

Function

í &G0

Guard tone disabled

&G1

550Hz guard tone enabled

&G2

1800Hz guard tone enabled

HELP SCREEN - CONTROLS

Type:

Immediate

Format:

<Ctrl> C, K or S

Description:

Cancel; or stop/restart scrolling of help screens

Command

Function

<Ctrl> C

Cancel display of help screen

<Ctrl> K

Cancel display of help screen

<Ctrl> S

Stop/restart scrolling of help screens

HOOK CONTROL

Type:

Immediate

Format:

AT [cmds] Hn [cmds]

Description:

Selects whether the modem is on-hook or off-hook

Command

Function

H0

Modem commanded to go on-hook (hang-up)

H1

Modem commanded to go off-hook (pick-up)

LIST DIAL COMMANDS

Type:

Immediate

Format:

AT [cmds] D$ [cmds]

Description:

Displays dial commands

LIST S-REGISTERS

Type:

Immediate

Format:

AT [cmds] S$ [cmds]

Description:

Displays the S-registers

ON-LINE

Type:

Immediate

Format:

AT [cmds] O [cmds]

Description:

Returns to on-line command (data transmission) mode.

Note: The O command must be placed at the end of the command string.

ON-LINE HELP

Type:

Immediate

Format:

AT [cmds] $ [cmds]

Description:

On-line help; displays basic command list.

PRODUCT CODE

Type:

Register

Format:

AT [cmds] S14 [cmds]

Description:

Stores product code, displayed in ATI0.

PULSE DIALING

Type:

Configuration

Format:

AT [cmds] P [cmds]

Description:

Enables pulse dialing

Note: This command can be duplicated with the P modifier in the D (Dial) command.

PULSE DIALING RATIO

Type:

Configuration

Format:

AT [cmds] &Pn [cmds]

Description:

Selects pulse dial make/break ratio

Command

Function

&P0

39/61ms at 10pps (North America)

&P1

33/67ms at 10pps (Europe)

RECEIVE-ONLY

Type:

Configuration

Format:

AT [cmds] Cn [cmds]

Description:

Sets receive-only; used if modem is attached to additional monitoring-only systems

Command

Function

C0

Disables transmitter

í C1

Enables transmitter

REPEAT COMMAND STRING

Type:

Configuration

Format:

AT [cmds] > [cmds]

Example:

AT>DT5551212 or ATDT5551212>

Description:

Causes modem to repeat command string until a keyboard key is pressed

Note: If used before or after the ATD command, the modem will redial the number until a connection is established or a maximum of ten attempts is reached.

REPEAT PREVIOUS COMMAND

Type:

Immediate

Format:

A/

Description:

Repeats previous command; mainly used for redial.

Note: Do not precede this command with AT, or follow it with <CR>.

REPORT INFORMATION

Type:

Immediate

Format:

AT [cmds] In [cmds]

Description:

Displays information requested

Command

Function

I0

Reports product code

I1

Reports ROM checksum

I2

Reports RAM test (OK or ERROR, followed by OK)

I3

Reports connection duration and real time

I4

Reports current command settings

RESULT CODES

Type:

Configuration

Format:

AT [cmds] Qn [cmds]

Description:

Enables modem to send result codes to the DTE

Command

Function

Q0

Result code sending enabled

Q1

Result code sending disabled

RESULT CODE FORMAT

Type:

Configuration

Format:

AT [cmds] Vn [cmds]

Description:

Selects word or numeric format for information-text and result codes

Command

Function

V0

Numeric format enabled

V1

Verbose (word) format enabled

SELECT CALL PROGRESS RESULT CODES

Type:

Configuration

Format:

AT [cmds] Xn [cmds]

Description:

Enables selection of tone detection and associated result code format options

Command

Function

X0

Busy and dial tone detection disabled; result codes 0-5 and 10 enabled.

í X1

Busy and dial tone detection disabled; result codes 0-5 and 10 enabled

X2

Busy tone detection disabled, dial tone detection enabled; result codes 0-6 and 10 enabled; also adaptive dialing, and fast dialing enabled.

X3

Busy tone detection enabled, dial tone detection disabled; result codes 0-5, 7-10 enabled; also adaptive dialing, wait for second dial tone, and wait for answer enabled.

X4

Busy and dial tone detection enabled; result codes 0-10 enabled; also adaptive dialing, wait for second dial tone, wait for answer, and fast dialing enabled.

X5

Busy tone detection enabled, dial tone detection disabled; result codes 0-5, 7-12 enabled; also adaptive dialing, wait for second dial tone, and wait for answer enabled.

X6

Busy and dial tone detection enabled; result codes 0-12 enabled; also adaptive dialing, wait for second dial tone, wait for answer, and fast dialing enabled.

Note: Valid numeric result codes; 0-8, and 10-12.

SOFT RESET

Type:

Immediate

Format:

AT [cmds] Zn [cmds]

Description:

Restores modem software default profile

SPEAKER MODE

Type:

Configuration

Format:

AT [cmds] Mn [cmds]

Description:

Selects various speaker options

Command

Function

M0

Speaker disabled

í M1

Speaker enabled until carrier signal detected

M2

Speaker enabled

M3

Speaker enabled following dialing, then disabled after carrier signal detected.

STATUS-REGISTER

Type:

Configuration

Format:

Read: AT [cmds] Sn? [cmds]

Write: AT [cmds] Sn=x [cmds]

Description:

Writes to or reads from a specified register

TEST MODES

Type:

Configuration

Format:

AT [cmds] S16=n [cmds]

Description:

Controls loopback tests, analog, digital, dial and self tests.

Command

Function

S16=0

Testing disabled

S16=1

Local analog loopback enabled

S16=2

Dial test (Factory testing only)

S16=4

Test pattern enabled (transmitted on CONNECT, either on answering or originate)

S16=5

Local analog loopback and test pattern enabled

TONE DIALING

Type:

Configuration

Format:

AT [cmds] T [cmds]

Description:

Enables tone dialing mode

Note: This command can be duplicated with the T modifier in the D (Dial) command.