User manual

Section 5

APPLICATIONS

5-1

5.0 APPLICATIONS

This Section describes some essential information about configuring the DPX-213 to

operate under various applications.

5.1 Resetting the Modem

Remove the lid from the box and short reset pads while switching the power on. This

executes a MASTER RESET which totally clears all stored numbers, stored commands,

passwords and S-registers from NVRAM and then loads the factory defaults from

EPROM.

5.2 Operating Modes

There are 4 operating modes on the DPX-213. The first two are asynchronous only and the

remaining two are synchronous operating modes.

NOTE: There is some interaction between the Data Terminal Ready (DTR) AT&Dn

commands and the AT&Mn operating Mode commands (as shown in the AT&Mn

command description tables).

The DPX-213 supports synchronous operation at 1200 bps in both CCITT and Bell Modes,

and 2400 bps in CCITT V.22bis Mode (to disable synchronous clocks, short J8 Pin 1 and

2). Before synchronous operation can be established, the correct AT commands must be

loaded with using an asynchronous terminal and the subsequent configuration stored in

NVRAM (EEPROM). The DPX-213 does not support V.25bis dialling methods. To enable

synchronous clocks, place a jumper across Pins 2 and 3.

Some special conditions exist for the two synchronous modes, AT&M2 and AT&M3. If

AT&D1 to AT&D3 is set, answering takes place when both the ring count and the DTR

high condition is reached. If the DTR lead is raised before the count stored in register S0,

the modem will go on-line in Originate Mode. If DTR is raised after S0 is reached (but

before the 8 second reset period stored in S0) the modem will go on-line in Answer Mode.

For all Synchronous Modes, the suggested starting values and sequences are: AT&F,

AT&C1, AT&D2, AT&M2 or AT&M3