Chapter 2 – AT Commands
Multi-Tech Systems, Inc. AT Commands Reference Guide (S000273G) 21
<max_codewords_tx> The decimal number from 256 to 2048 that specifies the
maximum number of code words which should be negotiated in the transmit
direction. Default = 2048
<max_codewords_rx> The decimal number from 256 to 2048 that specifies the
maximum number of code words which should be negotiated in the receive
direction. Default = 2048
<max_string_tx> The decimal number from 32 to 255 (maximum string length).
Command: +EB Break Handling in Error Control Operation
Description: This extended-format compound parameter controls the break handling in V.42 operation.
It accepts three numeric subparameters:
+EB=[<break_selection>[,<timed>[,<default_length>]]]
Subparameters: <break_seleIction> Decimal number 0 specifying that break is to be ignored; i.e., not
signaled to remote DCE.
<timed> Decimal number 0 specifying that any transmitted V.42 L-SIGNAL
will not indicate break signal length.
<default_length> Decimal number 0 specifying that break is not delivered to the DTE.
Report Commands: +EB? Reports current or selected values.
+EB=? Reports supported range of parameter values.
Command: +EFCS 32-bit Frame Check Sequence
Description: This extended-format numeric parameter controls the use of the 16-bit or 32-bit frame
check sequence (FCS) option in V.42.
Values: <value> Decimal number 0 specifying the use of the 16-bit FCS specified in V.42.
+EFCS? Reports current or selected values.
+EFCS=? Reports supported range of parameter values.
Command: +ER Error Control Reporting
Description: This extended-format numeric parameter controls whether or not the intermediate result
code is transmitted from the modem to the DTE.
S95 bit 3 is reset to 0 for +ER=0 and is set to a 1 for +ER=1. The more recent setting
of+ER or S95 bit 3, and the W command setting, determines the actual error control result
code reporting (see S95 Parameter and W Command).
Values: 0, 1
0 = Error control reporting disabled (no +ER intermediate result code transmitted).
1 = Error control reporting enabled (+ER intermediate result code transmitted).
Default: 0
Report Commands: +ER? Reports current or selected values.
+ER=? Reports supported range of parameter values.
Command: +ES Error Control Selection
Description: This extended-format command specifies the initial requested mode of operation when the
modem is operating as the originator, optionally specifies the acceptable fallback mode of
operation when the modem is operating as the originator, and optionally specifies the
acceptable fallback mode of operation when the modem is operating as the answerer.
It accepts three numeric subparameters:
+ES=[<orig_rqst>[,<orig_fbk>[,<ans_fbk>]]]
Subparameters: <orig_rqst> Decimal number which specifies the initial requested mode of operation
when the modem is operating as the originator. The options are:
0 Initiate call with Direct Mode.
1 Initiate call with Normal Mode (also referred to as Buffered Mode) only.
2 Initiate V.42 without Detection Phase. If V.8 is in use, disable V.42
Detection Phase.
3 Initiate V.42 with Detection Phase. Default
4 Initiate MNP.
7 Initiate Frame Tunneling Mode when connection is complete and Data
Mode is entered.