Index
132 025-9567E
Table 31. Number Restrictions for Instant Call Stacks
Panel Number Range
Small panel on encoder
0000 - 0004
0010 - 0014
0020 - 0024
0030 - 0034
0040 - 0044
0050 - 0053
Large Auxiliary panel, address 1 0100 - 0158
Large Auxiliary panel, address 2 0200 - 0258
Large Auxiliary panel, address 3 0300 - 0358
Each of the characters sent to the encoder will be echoed if they are valid. Invalid characters
will not be echoed. The next character should not be sent to the encoder until the last one has
been echoed, otherwise an overrun may occur. If available, an echo time-out should be used
by the computer program in case the character sent is invalid and not echoed. When the
encoder receives the CR (carriage return) following the four digits, the encoder will check to
see if the number represents a stack that has been programmed. If the instant call stack is not
programmed, then the encoder will respond with a NAK (negative acknowledge) control
character. If the instant call stack is programmed, then the encoder will start the calling
sequence. Each instant call stack may consist of one or more individual calls. The first step
performed by the encoder in sending an individual call via radio is to check the appropriate
channel busy input signal. While the input indicates that the channel is busy, the encoder will
output a BEL (bell) control character. The BEL will be issued approximately once a second
while the channel remains busy. If after 30 seconds, the channel is still busy, then the
encoder will give up the attempt to transmit the individual call, output an EOT (end-of-
transmission) control character, and will go on to the next call in the instant call stack.
During the 30-second channel busy delay, the computer can force the encoder to send the call
by transmitting a CR (carriage return) via the computer port. When all calls in the instant call
stack have been processed, the encoder will respond with an
ACK (acknowledge) control
character.
After the computer has initiated a calling sequence, it should not send any more characters to
the encoder until the encoder has either replied with an ACK or NAK (unless it is to force
transmission over a busy channel). Characters sent to the encoder when it is not idle will
cause an overrun and unpredictable results may occur. It should be noted that while the
encoder is being manually operated, it will output many characters via the
TX-DATA signal
that will be received by the computer. Therefore, a program that is used by the CAD to
control the encoder should clear out its serial port receive buffer prior to issuing a calling
command to the encoder. Also, while in the remote control mode the encoder's keypad can be
active at the same time as the computer port, therefore there is a chance that operator entries
from the keypad could inter-mix with CAD commands to the encoder. The asterisk character
(*) can be used by the computer to clear any information from the encoder that may have
previously been entered via keypad or computer. The encoder will give no character back to
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