In AX. 25 protocol, it detects the error on frames using CRC code. PASSALL command
determines how to process such errors, if found. If it’s ON, the error frame is accepted. If OFF is
selected only correct frames are accepted. Please leave this parameter OFF for error-free
communication.
4-4 Connected communication command
In the connected communication mode, in accordance with AX.25 protocol, the data is
exchanged with “Yes, I got it” or “I didn’t get it, please retransmit” kind of information. If the
reconfirmation (“I got it”) is not received after transmission, it retransmits the data.
In this chapter the following commands will be explained.
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Connect, Disconnect commands: CONNECT, DISCONE
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When the request of connection is received: CONOK, CMSG, CTEXT, CMSGDISC
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Retransmission related: RESPTIME, FRACK, RETRY, TRIES, CHECK, FIRMRNR
4-4-1 CONNECT command
abbrev. C default: not available parameter: destinations callsign VIA repeaters 1 to 8
example: C K6ANC-1
C K6ANC-1 VIA K6ANC-2
C K6ANC-1 V K6ANC-2, K6ANC-3
This will send a connect request frame (SABM). If the confirmation (UA frame) is received, “***
CONNECTED TO” followed by destination callsign and its repeater ID (if any) will appear on the
screen and a connection is established. Once connected, AX.25 protocol enables error-free
communications. If a UA frame is not received, it transmits a SABM frame up to a predetermined
number of times. If a UA frame is still not received, the TNC automatically disconnects.
Enter the destination callsign as shown in the example. The first example shows that you wish to
connect to K6ANC-1. As shown, you should add the SSID, as needed. You may also include a
relay stations’ callsign in case you cannot connect directly to the other station. In this case, you
can add VIA or V followed by the relay stations’ callsigns. Up to 8 stations can be specified for the
relay(s).
The last example shows that you are going to connect K6ANC-1 using K6ANC-2 and K6ANC-3 as
relay stations. Remember that the EJ-41U does not have a relay function so if you may need to
be a relay station yourself, please use an external TNC for that operation.
4-4-2 DISCONNE command
abbrev. D default: none parameter: none
example: D
This command sends a disconnect-request frame (DISC). When the reconfirmation frame(UA
frame) is received, the screen displays “****** DISCONNECTED” and goes to the disconnected
mode.