GAI-Tronics MRTI 2000 (No. PL1877A) Microprocessor Radio Telephone Interconnect Installation & Service Manual - Manual (Page 22)

Installation PL1877A Microprocessor Radio Telephone Interconnect
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Test 9 – HC11 DSP Communications
In this test, the HC11 and DSP communication paths are checked. The LEDs should display (in binary)
the value 0–253. A binary 255 or 254 indicates an error has occurred.
Test 10 – HC11 DSP Communications
In this test, each radio input is assigned a corresponding LED to indicate its state (active or inactive). If
the LED is lit, the input is active, if the LED is not lit the input is inactive. Beginning with the least
significant LED, the LEDs represent:
• PTT Sense Input (P1 pin 6)
• Carrier Detect Input (P1 pin 13)
• PL Detect Input (P1 pin 12)
• Patch Inhibit Input (P1 pin 15)
• Squelch Detect (Reduction of RX white noise)
• General Purpose Input 1 (P1 pin 7)
• General Purpose Input 2 (P1 pin 16)
• General Purpose Input 3 (P1 pin 14)
Test 11 – TX Audio Port
In this test the circuitry associated with TPL and DPL paging is checked. Upon entry into this test, the
PL1877A generates 1800 Hz at the parameter selected. Pressing the
UP button increments the output
level of the TPL or DPL signal. It also causes the new level to be saved to EEPROM.
Pressing the DOWN button decrements the output level of the TPL or DPL signal. It also causes the new
level to be saved to EEPROM.
Pressing the UP and DOWN buttons simultaneously switches from MDC (not applicable) to TPL to DPL
signal generation. The output level associated with the newly selected signaling type is written to the
circuitry. The most significant LEDs display binary 2 for TPL paging and binary 3 for DPL paging.
Pressing DOWN and PATCH ON/OFF while in TPL paging advances to the next TPL tone frequency.
Pressing this button combination while in DPL paging will have no effect.
Test 12 – RS-232 Diagnostic
This test requires that the TX and RX pins on the RS-232 port be shorted. In this test the PL1877A
transmits alternating patterns of 1’s and 0’s and expects to receive the exact same patterns. If the pattern
received matches the pattern sent, the four most significant LEDs will light. If the pattern does not
match, the LEDs remain unlit. The four least significant LEDs display the test number during this test.
Test 13 – DTMF Decode on Un-accessed Phone Line
During this test, phone DTMF is decoded and displayed in the five least significant LEDs (0 is displayed
as 0x10). The phone line is not accessed during this test.