Motorola 6864115B62-C Detailed Service Manual page 79

Table of Contents
Chapter 1 THEORY OF OPERATION
1.0 Controller Circuits ................................................................................................1-1
1.1 Overview.........................................................................................................1-1
1.2 General...........................................................................................................1-1
1.3 Radio Power Distribution ................................................................................1-2
1.4 Electronic ON/OFF .........................................................................................1-3
1.5 Emergency .....................................................................................................1-4
1.6 Mechanical ON/OFF.......................................................................................1-4
1.7 Ignition ............................................................................................................1-5
1.8 Microprocessor Clock Synthesizer .................................................................1-5
1.9 Serial Peripheral Interface (SPI).....................................................................1-5
1.10 SBEP Serial Interface.....................................................................................1-6
1.11 General Purpose Input/Output........................................................................1-6
1.12 Normal Microprocessor Operation..................................................................1-7
1.13 FLASH Electronically Erasable Programmable Memory ................................1-8
1.14 Electrically Erasable Programmable Memory (EEPROM)..............................1-9
1.15 Static Random Access Memory (SRAM)........................................................1-9
2.0 Controller Board Audio and Signalling Circuits ....................................................1-9
2.1 General - Audio Signalling Filter IC with Compander .....................................1-9
2.2 Transmit Audio Circuits ................................................................................1-10
2.3 Transmit Signalling Circuits ..........................................................................1-12
2.4 Receive Audio Circuits .................................................................................1-14
2.5 Receive Signalling Circuits ...........................................................................1-17
2.6 Voice Storage ...............................................................................................1-18
Chapter 2 TROUBLESHOOTING CHARTS
1.0 Controller ............................................................................................................2-1
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