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4-6
Controller Theory of Operation:
Microprocessor Circuitry
4.3.5
Sensing of VOX operating
Port PTT2 (Pin 68) is used to detect the presence of VOX operating when externally connected
accessories with VOX enabled. When port PTT2 is low, the VOX will start to operate.
4.3.6
Microprocessor Power-on reset Routine
On power-up, the microprocessor is held in reset until the digital 3.3V regulator (U506 Pin 4)
provides a stable supply voltage. Once the digital supply reaches steady state and releases the reset
line (U107 Pin 2), the microprocessor begins to start up. After reset release by all circuit, the
software within the microprocessor begins executing port assignment, RAM checking, and
initialization.
4.3.7
Microprocessor 7.3728 MHz Clock
The 7.3728 MHz clock signal (Pin 13, X-in) is provided from the FL101.
4.3.8
Battery indicator
Various battery types are available having different capacities. The radio can select different battery
type by FPP (Front Panel Programming) or CPS. A voltage divided by R153 and R154. And
EEPROM have a data for each battery types.
Summary of Contents for P100 Series
Page 1: ...P100 Series Portable Radios Detailed Service Manual ...
Page 2: ......
Page 8: ...iv Notes ...
Page 18: ...xiv List of Tables Notes ...
Page 22: ...xviii Summary of Printed Circuit Boards and Bands Available Notes ...
Page 30: ...Notes 2 4 Test Equipment Service Aids and Service Tools Service Aids ...
Page 54: ...7 4 UHF2 Schematic Diagrams Overlays and Parts Lists Speaker and Microphone Schematic Notes ...
Page 128: ...7 78 Circuit Board Schematic Diagram and Parts List UHF2 435 480 MHz Notes ...
Page 150: ...7 100 Circuit Board Schematic Diagram and Parts List UHF2 MDC QCII R TTE 435 470 MHz Notes ...
Page 166: ...10 4 VHF Schematic Diagrams Overlays and Parts Lists Speaker and Microphone Schematic Notes ...
Page 192: ...10 26 Circuit Board Schematic Diagram and Parts List VHF 136 174 MHz Notes ...
Page 218: ...10 52 Circuit Board Schematic Diagram and Parts List VHF 136 174 MHz Notes ...
Page 242: ...10 76 Circuit Board Schematic Diagram and Parts List VHF MDC QCII R TTE 136 174 MHz Notes ...
Page 258: ...13 4 UHF1 Schematic Diagrams Overlays and Parts Lists Speaker and Microphone Schematic Notes ...
Page 328: ...13 74 Circuit Board Schematic Diagram and Parts List UHF1 MDC QCII R TTE 403 447 MHz Notes ...
Page 332: ...A 4 Warranty Service Support and Replacement Parts Further Assistance From Motorola Notes ...
Page 335: ......