GAI-Tronics MRTI 2000 (No. PL1877A) Microprocessor Radio Telephone Interconnect Installation & Service Manual - Manual (Page 85)

PL1877A Microprocessor Radio Telephone Interconnect Parameter Modification
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Modem Operator Instructions
To access the remote terminal programming (modem) feature of the PL1877A, connect a standard DTMF
telephone in parallel with the originating modem. From the telephone, dial the phone number of the
remote PL1877A. While listening on the telephone, wait until the PL1877A seizes the line and returns a
prompting tone (beep) to the caller. The amount of rings and the length of time vary depending on
parameter programming.
At the beep, enter the sequence *#2. If the landline security code has been enabled, it must be entered as
a prefix to this command (see parameters 145–150). Next, type the command +++ATA at the computer
keyboard. The PL1877A connects approximately 2 seconds after the answer tone. Once access has been
gained, changing or viewing of operating parameters can proceed as described under Parameter
Modification via RS-232.
N OTE : If the PL1877A is configured for land-line selective signaling and you wish to allow modem
programming, you must program the PL1877A to require a * access command from the land-line caller
(parameters 43, 50). Then, to use the modem, dial *#2 (along with any required prefix) instead of *. If
you do not program the PL1877A to require a * access command, the PL1877A interprets *#2 as paging
input instead of a command to enter the modem programming mode.
DTMF Programming Feature
Operator Instructions
Limited programming of the PL1877A is provided from either a standard DTMF (Touch-Code)
telephone, or from a mobile or portable radio equipped with a Touch-Code pad. The PL1877A may be
programmed to require an access code prefix to provide additional protection against accidental
modifications of parameters. This code may be different for mobile (or portable) and land-line parameter
modification.
Parameter 21 enables or disables remote programming of parameters via DTMF telephone. The default
for this parameter is enabled (parameter 21 = 1). Parameter 57 enables or disables mobile DTMF
programming of parameters. The default for this parameter is disabled (parameter 57 = 0).
A second PL1877A, or similar device for decoding DTMF digits, is required to display the DTMF digits
from the remote programming telephone location. This PL1877A should be placed in parallel with the
calling telephone instrument, using a modular “T” adapter, similar to the installation of an answering
machine. The PL1877A should also be placed in diagnostic Test 13 to allow displaying of any valid
DTMF digit.