User`s manual

The following configurations are controlled by AT commands:
Mode : Switched / Leased
Rate: 56K / 64K Clear Channel
Loopbacks: Local Loopback
Remote Terminal
RTS: Normal (follow DTE’s RTS)
Forced High
CTS: Normal Mode (follows RTS)
Off during No Signal Condition
DCD: Normal Mode (Off during Control Mode Idle (CMI)
Forced High
DSR: Off during No Signal Condition condition
Forced High
Refer to Appendix E, “CSU/DSU Tests.”
The AT codes and commands are shown below and on the following page.
* - indicates powerup default
•- indicates powerup configuration is defined by DIP switches
Code Command Related S Register
AT Attention command
D Dial Telephone number
Dial Modifiers
0-9 Numbers to dial
, Pause 2 seconds
H Hang-up Call
I Display product code
I1 Display ROM checksum
I2 Display Firmware Revision Level
O Return to Data mode
Sr? Display register r value
Sr=n Set register r to value n
Code Command Related S Register
V0 Send numeric responses S14
V1 * Send word responses S14
&C0 Force DCD on S21
&C1 * Normal DCD S21
&C2 Normal DCD; CTS off when DCD off S21
&D0 • DTR off: Cmd mode; DTR on: Data mode S21
&D1 Dropping DTR enters command mode S21
&D2 • Dropping DTR terminates call S21
&F0 Factory Configuration 0 - 56K leased line
&F1 Factory Configuration 1 - Switched 56K line
&F2 Factory Configuration 2 - Clear Channel 64K leased
&L0 • Switched 56K Service S27
&L1 • Leased Line S27
&N0 • 56K rate S27
&N1 • 64K rate S27
&R0 * Normal RTS S21
&R1 Force RTS on S21
&S0 Force DSR on S21
&S1 * Normal DSR S21
&T0 End test in progress
&T1 Local Loop (LL) S16