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Chapter 4 - V.22bis Commands
V.22bis Synchronous Access Mode Commands
Three commands support Synchronous Access Mode:
+ES enables and disables Synchronous Access Mode in the client or central site modem. Enabling Synchronous Access Mode enables the use of the
+ESA configures the operation of the Synchronous Access Submode +ITF selects Transmit Flow Control Thresholds
+ESA Configure Synchronous Access Submode
The operation of the Synchronous Access
This
Syntax
+ESA=[<trans_idle>[,<framed_idle>[,<framed_un_ov>[,<hd_auto>[,<crc_type>[,<nrzi_en>[,<syn1>[,<syn2>]]]]]]]]
Defined Values
<trans_idle> | Specifies the bit sequence transmitted by the modem when a transmit data buffer under run |
| condition occurs, while operating in Transparent |
0In Transparent
<framed_idle> Specifies the bit sequence transmitted by the modem when a transmit data buffer under run condition occurs immediately after a flag, while operating in Framed
0 In Framed
condition occurs immediately after a
0In Framed
1In Framed
<hd_auto> | This subparameter should not be commanded. |
<crc_type> | Specifies the CRC polynomial used while operating in Framed |
0CRC generation and checking disabled (default).
1In Framed
| and checked by the modem in the receive direction. |
<nrzi_en> | 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). |
<syn1>, <syn2> | Specifies the octet value(s) to be used while performing |
commanded to 255 (FFh); <syn2> is not to be commanded.
Reporting Selected Options
The modem reports the selected options in response to the following command: +ESA?
The response is: +ESA:
<trans_idle>,<framed_idle>,<framed_un_ov>,<hd_auto>,<crc_type>,<nrzi_en>,<syn1>,<syn2> Example:
+ESA?
+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: +ESA=?
The response is:
+ESA: (list of supported <trans_idle> values), (list of supported <framed_idle>values),(list of supported
<framed_un_ov> values), (list of supported <hd_auto>values),(list of supported <crc_type> values), (list of supported <nrzi_en> values),(list of supported <syn1> values), (list of supported <syn2> values)
Example:
+ESA=?
+ESA:
31 |