User manual

Section 8

S REGISTERS

8-1

8.0 S REGISTERS

The "S" registers, or status registers store the modem configuration parameters. The S

registers (particularly the bit mapped registers) are usually only altered using the AT

commands, but in exceptional circumstances may require alteration via the ATSr=n

command. S registers should be altered with care, as it is possible to configure the modem

with conflicting parameters producing unpredictable results. Should altering the S registers

produce erratic operation, reload the factory default settings using the AT&F command.

The DPX-213 uses 24 "S" registers.

This Section contains information on the bit mapped registers used in the DPX-213. These

registers are set and reset by the various AT commands.

To change the contents of a bit-mapped register, you must change the appropriate bits,

recalculate the decimal value to reflect those changes and then set to the new value to

initiate the changes. Changing a bit-mapped S-Register involves the following steps:

1. The binary notation system is used in the following example. A simple system for

converting 8 bit binary representations into their decimal equivalents is given

here. In order to perform the following steps, you will need a copy of the table

given below.

BIT:

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

Current Setting :

New Setting : TOTAL

Decimal Equivalent

Underline for bits set to '1'

128 64 32 16 8 4 2 1

Table 8.1 Table for Converting 8 Bit Binary to Decimals

2. Use the ATSr? command to display the particular S-register value you wish to

change (where r equals the S-reg value you wish to display between 0 and 34).

3. From the display, determine the corresponding 8 bit representation. Insert the bit

values in the row 'Current Setting' using the table given above.

4. Determine those bits you need to change by changing the bit values as

appropriate. To achieve this, you will need to refer to the appropriate S-register

description. Insert the new bit values in the row 'New Setting' using the table

given above. The new binary number should include those bit values which have

not changed.