Comtrol AT Commands for SmartACFL User Manual
Page 72

Command Reference Manual
3-52
Conexant
100722A
3.2.8.1 +ESA - Configure Synchronous Access Submode
The operation of the Synchronous Access sub-Mode is configured by the +ESA parameter.
This extended-format compound parameter is used to control the manner of operation of the Synchronous Access Mode in
the modem. It accepts six numeric subparameters:
Syntax
+ESA=[
Defined Values
Specifies the bit sequence transmitted by the modem when a transmit data buffer underrun
condition occurs, while operating in Transparent sub-Mode. The options are:
0
In Transparent sub-Mode, modem transmits 8-bit SYN sequence on idle. Modem receiver
does not hunt for synchronization sequence (default and fixed).
Specifies the bit sequence transmitted by the modem when a transmit data buffer underrun
condition occurs immediately after a flag, while operating in Framed sub-Mode. The options are:
0
In Framed sub-Mode, modem transmits HDLC flags on idle (default and fixed).
Specifies the actions undertaken by the modem when a transmit data buffer underrun or overrun
condition occurs immediately after a non-flag octet, while operating in Framed sub-Mode.
0
In Framed sub-Mode, modem transmits abort on underrun in middle of frame (default).
1
In Framed sub-Mode, DCE transmits a flag on underrun in middle of frame, and notifies
DTE of underrun or overrun.
Specifies whether or not, in V.34 half-duplex operation, additional procedures besides those
specified in § 12/V.34 shall be performed by the modem when switching from primary channel to
secondary channel operation, and vice versa. This subparameter should not be commanded.
Specifies the CRC polynomial used while operating in Framed sub-Mode. The options are:
0
CRC generation and checking disabled (default).
1
In Framed sub-Mode, the 16-bit CRC is generated by the modem in the transmit direction,
and checked by the modem in the receive direction.
Specifies if Non Return to Zero Inverted (NRZI) encoding is to be used by the modem for transmit
and receive data. The options are:
0
NZRI encoding and decoding disabled (default and fixed).
Specifies the octet value(s) to be used while performing character-oriented framing.
be commanded to 255 (FFh);