Chapter 4 - AT Commands, S-Registers, and Result Codes

*The MTA128ST-USB is manufactured in two builds. To determine the build of your terminal adapter (TA), issue the ATI2 command in a terminal window. If the TA responds to the command with MTA128ST-USB, then it supports V.110. If your TA resonds to the ATI2 command with MTA128ST-USB-RC, V.110 support is not available. The MTA128ST-USB-RC will respond to the &F1 command with an ERROR..

Command:

&Jn

Function:

Automatic Channel Bundling

Values:

n = 0 or 1

Default:

n/a

Description: &J1 causes the TA to dial the number given in the dial string again to set up

 

a bundled PPP connection (also known as MultiLink PPP). Only works with

 

the PPP/ML-PPP protocol (!Z=9). &J0 will not dial the given number again

 

and it will not interfere with the given dial string meaning that if there are two

 

numbers in the dial string (like ATD5551000&5553000) the TA will dial both

 

of those numbers. &J0 does not disable the dialing of a second number if a

 

second number is given in the dial string.

 

n=0

disables automatic channel bundling

 

n=1

enables automatic channel bundling

Command: &Rn

 

Function:

CTS Control

Values:

n = 0, 1, or 2

Default:

&R1 (CTS forced high)

Description: Allows you control the state of the CTS (Clear to Send) signal on the

 

RS232E/V.24 interface. Normally the CTS signal follows the state of the RTS

 

signal when the MTA128ST-USB is online.

 

&R0 CTS acts normally; i.e., it follows RTS

 

&R1 CTS is forced high, but still provides online flow control

 

&R2 CTS is forced high, but it drops on disconnect for the period of time

 

set by S10. CTS still provides flow control when the TA is online.

Command: &Sn

 

Function:

DSR Control

Values:

n = 0, 1, or 2

Default:

&S0 (DSR high)

Description: Controls state of DSR (Data Set Ready) signal on RS232E/V.24 nterface. A high DSR signal indicates to the computer that TA is ready to transmit data. &S0 DSR is always high.

&S1 DSR acts normally; that is, it follows the state of the CD signal, which goes high when the MTA128ST-USB detects a carrier signal, and goes low when the carrier signal is lost.

&S2 DSR is always high, except on disconnect, when it drops for the period of time set by S10 and then goes high again.

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