Epson Multi-mode Data Controller MFJ-1278B - Manual (Page 177)

MFJ-1278B MULTI-MODE OPERATIONAL COMMANDS
ACKPRIORITY ON/OFF Mode: Packet Default: ON
ACKPRIORITY permits an acknowledging TNC to transmit without regard to the slotting
delay. Turning ACKPRIORiyty ON to enable prioritized acknowledgement.
If ACKprior is turned off and SLots (see SLots) is set to 0, the modified AX.25 protocol is
effectively disabled. The MFJ-1278B will behave like normal AX.25 protocol.
Prioritized acknowledgments and slotted channel access can be enabled or disabled
independently of one another. So you could if you wished run normal AX.25 with slotted
channel access or the new protocol without slotted channel access.
ACKTIME nnnn
Mode: Packet Default: 14
Parameters:
nnnn 0-250, in 10 ms intervals.
The ACKTIME parameter controls a delay that occurs whenever any packets have been
received by the MFJ-1278B that are not addressed to the MFJ-1278B.
ACKTIME should be calculated by the radio channel baud rate, and by the keyup and
keydown (TXDELAY and fixed timer, in TNC) delays. It should reflect the time it takes for
an acknowledging TNC on the channel to keyup, send it's acknowledgement, and release the
PTT. This represents the time required to send a response frame, with no I field appended, at
the baud rate being used on the radio port.
The current 140 millisecond default is close but should be adjusted for 1200 baud work to
130 milliseconds (ACKTime set to 13).
For 300 baud HF work this parameter should be set to 520 milliseconds (ACKTime set to
52).
ALOCKCHAR nn
Mode: CW/MCW Default: $15
This command controls which character is used to force the MFJ-1278B to lock its CW
receive speed to the incoming receive signal. See CW operating instructions for more detail
information when using ALOCKCHAR. Control-U is the default value for the
ALOCKCHAR command.