4 AT Commands, S-Registers, and Result Codes
43
S37 decimal 0–19 0 Sets the maximum V.34 “upstream” speed at
which the modem attempts to connect.
0= maximum modem speed
1= reserved
2= 1200/75 bps
3= 300 bps
4= reserved
5= 1200 bps
6= 2400 bps
7= 4800 bps
8= 7200 bps
9= 9600 bps
10= 12000 bps
11= 14400 bps
12= 16800 bps
13= 19200 bps
14= 21600 bps
15= 24000 bps
16= 26400 bps
17= 28800 bps
18= 31200 bps
19= 33600 bps
S38 decimal 0–23 1 Sets the maximum 56K “downstream” speed
at which the modem attempts to connect.
The default maximum speed is 56K bps.
Value V.90 mode K56flex mode
0 56K disabled 56K disabled
1 56K autorate 56K autorate
2 28000 bps 32000 bps
3 29333 bps 34000 bps
4 30666 bps 36000 bps
5 32000 bps 38000 bps
6 33333 bps 40000 bps
7 34666 bps 42000 bps
8 36000 bps 44000 bps
9 37333 bps 46000 bps
10 38666 bps 48000 bps
11 40000 bps 50000 bps
12 41333 bps 52000 bps
13 42666 bps 54000 bps
14 44000 bps 56000 bps
15 45333 bps
16 46666 bps
17 48000 bps
18 49333 bps
19 50666 bps
20 52000 bps
21 53333 bps
22 54666 bps
23 56000 bps
Register Unit Range Default Description