Chapter 3 - AT Commands
$En | V.42 Error Correction at 300 bps |
| n = 0 or 1 |
| Default: $E0 |
| At 300 bps, error correction is not normally used. |
| $E0 disables 300 bps/V.42 error correction altogether. |
| $E1 enables the modem to function at 300 bps in |
| (&E1), or reliable (&E2) mode. |
$An | Autoreliable Buffering |
| n = 0 or 1 |
| Default: $A0 |
| In autoreliable mode, the modem has four seconds to establish a reliable connection, after |
| which the modem drops to |
| will normally be discarded. The $A command causes the modem to buffer (store) data that |
| is received during the autoreliable |
| after the CONNECT message. |
| $A0 discards the data received during the autoreliable |
| $A1 buffers data received during the autoreliable |
$Fn | Autoreliable Fallback Character Enable/Disable |
| n = 0 or 1 |
| Default: $F0 |
| In autoreliable mode, the modem has four seconds to establish a reliable connection. If a |
| single carriage return is received from the remote modem during this period, the |
| autoreliable modem assumes that the remote modem is not in reliable mode, and drops to |
| |
| to drop to |
| Use the $F command to enable this feature. |
| You can use the autoreliable fallback character ($F) and autoreliable buffering ($A) |
| commands together to cause the modem to buffer all data received up until the carriage |
| return, and then drop to |
| following the CONNECT message. |
| $F0 causes the modem not to fall back to |
| received. |
| $F1 causes the modem to fall back to |
| received. |
$Rn | Retransmit Count |
| n = 0 or 1 |
| Default: $R0 |
| If errors are received during a reliable connection, the modem |
| that contained an error. If another error occurs, it |
| counts the number of times that a data block is |
| $R0 causes the modem to disconnect if the same block of data is |
| being received properly, on the assumption that the line is unsuitable for transmission. |
| $R1 causes the modem to disable the retransmit counter, so that the modem keeps trying to |
| send data and will not abort, no matter how many times the same block is resent. Type |
| AT$R0 to disconnect the modem if all attempts to |
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