3Com 56k User's Manual And Reference page 71

Register Default
S27 (Continued)
S28 0
8
255
S29 20
S30 0
S31 128
S32 2
Technical Reference
Function
Bit Value Result
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
Eliminates the V.32 answer tones for a faster connection
Default item, all times are in tenths of seconds
Disables all connections except V.32 at 9600 bps
Sets the duration, in tenths of a second, of the V.21 answer mode fallback timer
Reserved
Reserved
Bit-mapped register setup
To set the register, see the instructions for S13
Bit Value Result
0 1 V.8 Call Indicate enabled
1 2 Enables V.8 mode
2 4 Reserved
3 8 Disable V.34 modulation
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