User guide

V.250 AT COMMANDS
AT Commands for EV-DO-EV3 Modems
50
Syntax
Command Command type
ATS25=[<time>] Set
ATS25? Read
Parameters and Values
<time> Expressed in hundredths of a second.
0-255 Default: 5.
Note: The delay is effective only if its value is greater than 5.
Error Control
Error Control Selection +ES
Set command sets the manner of operation of the modem’s V.42 protocol.
Read command reports the current V.42 error control setting value in the format:
+ES: <orig_req>,<orig_fallback>,<ans_fallback>
Test command returns all supported values of the <orig_req>, <orig_fallback>, <ans_fallback> parameters.
Syntax
Command Command type
AT+ES[=<orig_req>,<orig_fallback>,<ans_fallback>] Set
AT+ES? Read
AT+ES=? Test
Parameters and Values
<orig_reg> Specifies the initial request mode of operation when originating a call.
0 Direct mode.
1 Initiate call with buffer mode only.
2 Initiate V.42 without detection phase. If V.8 is in use, this is a request to disable
V.42 detection phase.
3 Initiate V.42 with detection phase. Default: 3.
4 Initiate alternative protocol.
<orig_fallback> Specifies the acceptable fallback mode of operation when originating a call.
0 Error control optional; if error control can not be established, use buffered mode
with flow control. Default: 0.
1 Error control optional; if error control can not be established, change data rate to
match line <carrier> rate and use direct mode.
2 Error control required; if error control cannot be established, disconnect.
3 Error control (LAPM) required; if LAPM cannot be established, disconnect.
4 Error control (alternate MNP) required; if MNP cannot be established, disconnect.
<ans_fallback> Specifies the acceptable fallback mode of operation when answering a call.
0 Direct mode.
1 Error control disabled, use buffer mode.
2 Error control optional; if error control cannot be established, use buffer mode with
flow control. Default: 2.