Hardware manual

5901 High Speed Dialup Modem Hardware Manual

October 19, 2007

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.

d 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.

e 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.

f 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).

g, h Specifies the octet value(s) to be used while performing character-oriented framing, where g

is to be commanded to 255 (FFh); h is not to be commanded.

Reporting Selected Options

The modem reports the selected options in response to the following command:

Command: +ESA?

Response: +ESA:a,b,c,d,e,f,g,h

Example: +ESA: 0,0,0, ,0,0,255, for the defaults.

Reporting Supported Options

The modem reports the supported options in response to the following command:

Command: +ESA=?

Response: +ESA: (list of supported a values), (list of supported b values),

(list of supported c values), (list of supported d values),

(list of supported e values), (list of supported f values),

(list of supported g values), (list of supported h values)

Example: +ESA: (0),(0),(0-1), ,(0-1),(0),(255),

10.4.10 +ESR=n - Selective Repeat

This extended-format numeric parameter controls the use of the selective repeat (SREJ) option in

V.42.

Command: +ESR=[n] Decimal number 0 specifying that SREJ is not used.

Example: +ESR: (0) For default settings.