Operating instructions

TECHNICAL QUICK REFERENCE

152

S27 0 Bit-mapped register setup. To set the register, see instructions for S13.

Bit Value Result

0 1 Enables ITU-T V.21 modulation at 300 bps for

overseas calls; in V.21 mode, the modem answers

both overseas and domestic (U.S. and Canada) calls,

but only originates V.21 calls. (Default Bell 103)

1 2 Enables unencoded (non-trellis coded) modulation in

V.32 mode.

2 4 Disables V.32 modulation.

3 8 Disables 2100 Hz answer tone to allow two V.42

modems to connect faster.

4 16 Enables V.23 fallback mode.

5 32 Disables V.32bis mode.

6 64 Disable V.42 selective reject.

7 128 Software compatibility mode. This setting disables the

codes and displays the 9600 code instead. The actual

rate of the call can be viewed on the ATI6 screen.

Used for unusual software incompatibilities. Some

software may not accept 7200, 12,000, and 14,400

bps or greater result codes.