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accepted. Please leave this parameter OFF for error-free communication.
4-4 Connected for 2way communications (being connected)
In the connected communication mode, in accordance with the AX.25 protocol, data is exchanged with “Yes, I
got it” or “I didn’t get it, please retransmit” kind of information. If the confirmation (“I got it”) is not received
after transmission, the TNC retransmits the data.
In this chapter the following commands will be explained.
Connect, Disconnect commands: CONNECT, DISCONE
When a request for connection is received: CONOK, CMSG, CTEXT, CMSGDISC
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 connecting 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-50U 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.
4-4-3 to 4-4-6 intentionally deleted (for commercial use only)
4-4-6 RESPTIME command
Abbrev: RES default: 5 parameter: 0-250
example: RES 5
In the connected packet mode, your TNC must reply to the destination by saying “Yes, I got your packet”(RR
frame) after the information (I frame) was correctly received. Up to 7 RR frames can be sent together at one time.
For example, you can reduce the RR frame transmission during a file transaction when different I frames are
received frequently. This command sets the waiting time between the reception of an I frame and transmission of
a RR frame in units of 100 ms. The communication efficiency may become poor if a higher number is set as the
time delay to send RR becomes longer. If an even higher number is set, an I frame may be sent before an RR frame
