Kantronics MT1200, Руководство пользователя

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AX25L2V2 {ON | OFF}
default ON
This command provides compatibility with all known packet units implementing AX.25
protocol. When ON, Level 2 Version 2 protocol is implemented and the TNC will
automatically adapt to whichever version the connecting station is using. When OFF,
Level 2 Version 1 is implemented. Set this command to OFF if you need to digipeat
through other units, which do not digipeat version 2 packets. You may also find benefit
from setting this command OFF when using several digipeaters (not nodes) to send
packets, or when conditions are marginal between the two stations involved. (NOTE:
Changing this setting after connecting to another station will have no effect on the
current connection.)
The major difference in V1 and V2 protocol is the method used to handle retries. In the
connected mode, if a packet is sent and not acknowledged, Version 1 will re-send the
entire packet and then disconnect if the RETRY count is reached. Version 2 will first
send a poll, the response to this poll will determine if the packet was received. It is
possible that the ack was collided with and therefore the data packet does not need to
be resent. If the ACK shows that the data packet was not received, it will be re-
transmitted. Each time a poll is answered the TRIES count is reset to 0. If the RETRY
count is reached, version 2 will attempt to re-connect unless RELINK is OFF. If the re-
connect attempt is unsuccessful, then version 2 will issue a disconnect.
See also: RELINK, RETRY, TRIES
For more information, see the book AX.25 Amateur Packet-Radio Link-Layer Protocol
Version 2.0 October 1984 , which can be obtained from the ARRL.
AXDELAY n (n = 0 – 255)
default 0
The value of “n” is the number of 10 millisecond intervals to wait, in addition to
TXDELAY, after keying the transmitter before data is sent. This delay can be helpful
when operating packet through a standard “voice” repeater, or when using an external
linear amplifier which requires extra key-up time. Repeaters using slow mechanical
relays, split-sites, or both require some amount of time to get RF on the air.
See also: AXHANG
AXHANG n (n = 0 - 255)
default 0
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