Monroe Electronics 948A - Manual (Page 19)

18
CODE SELECTION
The hexadecimal rotary switches on the front edge of the 3185E determine each digit in the
code sequence. 0 through D select the corresponding DTMF digit to be decoded. The letter
'E' on the rotary switch represents the '*' DTMF digit and the letter 'F' on the rotary switch
represents the '#' DTMF digit.
As stated before, the 3185E is factory set to decode a 4-digit 'ON' code sequence and a 4-
digit 'OFF' code sequence. The first three digits of the code sequence are the same for 'ON'
and 'OFF' commands. The fourth digit for the 'ON' code sequence is factory set to '*', and the
fourth digit for the 'OFF' code sequence is factory set to '#'.
It is not necessary to power down the 3185E when you are programming the code sequence.
The 3185E program will read the switch settings each time a code sequence is received.
Consult FIGURE 1 on page 4 for location of switches and their designations.
OPERATION
When the 3185E is connected to a DC power source, the Power/Valid Digit LED CR14 on the
front edge of the PC board will be illuminated. This LED indicator will continue to illuminate
until a valid DTMF digit is detected or DC power is removed from the board.
The Valid Sequence LED CR15 will illuminate upon the decoding of a correct DTMF code
tone pair in the proper sequence. Upon the fourth correct digit, the output relay activates and
the Relay Output LED CR13 illuminates.
During the reception of valid DTMF tone pairs in a sequence the 3185E will — after decoding
a valid code number — wait for the next valid code in the sequence. If the time between
digits is more than 3 seconds, the 3185E will reset and require that the sequence be sent
completely again.
Operating With a 4-Digit Code:
When a 4-digit code sequence is selected on the 3185E the switch program will be as follows:
SWITCH 1 = first digit of the code sequence for both 'ON' and 'OFF'.
SWITCH 2 = second digit of the code sequence for both 'ON' and 'OFF'.
SWITCH 3 = third digit of the code sequence for both 'ON' and 'OFF'.
SWITCH 4 = fourth digit of the code sequence for 'ON' (preset to '*' if switch not installed).
SWITCH 5 = fourth digit of the code sequence for 'OFF' (preset to '#' if switch not installed).
If the 3185E is programmed for momentary relay output or alternating relay action SWITCH 5
is not used for programming.