17
is sent.
4-4-7 FRACK command
Abbrev. FR default: 3 parameter: 0-250
example: FR 5
When you are “on-line” (connected) and the transmitted information frame (I frame) is received at its
destination correctly, you receive a “Yes, I got it” (RR frame). If a certain time has elapsed but you still don’t get
a reply, the I frame will be transmitted again (retry feature). Beside I frames, and a connection request frame
(SABM frame), there are frames that require a reconfirmation from the destination. The retry will take place if a
reply is not received. This command sets the time duration between the end of transmission of the reply-required
signal and the start time of a retry transmission in 1 second.
When a relay station is involved, it automatically waits for a [(number of relay stations X 2 + 1) X parameter]
period. The relay stations only pass the messages, and they do not acknowledge each packet. Accordingly, the
transmitted packet takes some time until it gets to the destination and a reply comes back.
This unit automatically changes the retry fraction time in accordance with the number of relay stations. In a case
where packet traffic is very high, set this parameter a little higher than the default. It eliminates unnecessary
retries when traffic is reduced.
4-4-8 RETRY command
Abbrev. RE default 10 parameter: 0-15
example: RE 15
This command is used to set the maximum number of retries. When the maximum number of retries exceeds the
parameter, [****** retry count exceeded],[***** DISCONNECTED] appears on the screen, and the TNC returns
to the disconnected state. The conventional TNC AX.25 protocol may transmit a SABM frame at this point, and
the RELINK command (default OFF) is available to set this option. The EJ-50U does not have this parameter
(fixed at OFF position).
4-4-9 TRIES command
Abbrev. TRI default: 0 parameter: 0-15
example: TRI 0
This is to display and adjust the current retry counter. If the command TRIES is entered, it might report back
TRIES 9. You can enter TRIES 2 and in doing so, you reset the number of TRIES before reaching the cutoff figure
set under RETRY.
4-4-10 CHECK command
Abbrev. CH default 30 parameter: 0-250
example CH12
When connected, even without sending data, this command sends a message to the effect of “Are you still
there?” to check if the link is still present. This parameter sets the time between the sending of the check-packet
(“Are you still there?”) after the destination’s signal is received, in 10 ms unit.
4-4-11 FIRMRNR command
Abbrev.: FIR default: OFF parameter: ON/OFF
example: FIR ON
When the “Wait a moment!” message (RNR frame= not available for reception) is received from the destination,
this parameter determines how your station will proceed with sending your packet.
When the setting is in the ON position and you receive RNR frame, it does not transmit the packet until you
receive another frame from the destination. In the OFF position, it will transmit the packet regardless of the RNR
