Black Box MD1641A, MD1640A manual Retransmit Count $R

SERIES II INTELLIGENT DATA/FAX MODEMS

The $F command can be used to disable this fallback-to-Normal-due-to- CARRIAGE-RETURN feature.

The Auto-Reliable fallback character ($F) and Auto Reliable buffering ($A) commands can be used together to cause the modem to buffer all data received up until the CARRIAGE RETURN, and then drop to Normal mode. All data received will then be output following the CONNECT message.

AT$F0 = Do not fall back to Normal if CARRIAGE RETURN received.

AT$F1 = Fall back to Normal mode if CARRIAGE RETURN received.

The factory default is $F0.

Retransmit Count $R

If errors are received during a Reliable connection, the modem re-sends the block of data which contained an error. With the $R0 command, if another error occurs, the block will be re-sent again. The modem counts the number of times that a data block is re-sent. If the same block of data is resent 12 times and still has not been received properly, the modem assumes that the transmission line is unsuitable for transmission, and abort the connection.

This retransmit counter is disabled by the $R1 command. When the retransmit counter is disabled, the modem keeps trying to send data and will not abort, no matter how many times the same block is resent.

AT$R0 = Disconnect if retransmit count is exceeded.

AT$R1 = Do not disconnect due to retransmits.

The factory default setting is $R0.

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