Motorola ASTRO W3 Service Manual page 6

iv
3.1.5 On-/Off-Hook Control ........................................................................................................ 3-3
3.1.6 Backlight Circuit ................................................................................................................ 3-3
3.1.7 Power Supply.................................................................................................................... 3-3
3.1.8 Status LEDs ...................................................................................................................... 3-3
3.1.9 Jumper Selection .............................................................................................................. 3-3
3.1.10 Power On/Off .................................................................................................................... 3-4
3.1.11 Miscellaneous Functions................................................................................................... 3-4
3.2 W4, W5, and W7 Control Heads.................................................................................................... 3-4
3.2.1 Power Switch/Ignition........................................................................................................ 3-4
3.2.2 Voltage Regulator ............................................................................................................. 3-5
3.2.3 Microcomputer .................................................................................................................. 3-5
3.2.4 Interface Circuitry.............................................................................................................. 3-5
3.2.5 Reset................................................................................................................................. 3-6
3.2.6 Bus Busy........................................................................................................................... 3-6
3.2.7 Serial Bus Data ................................................................................................................. 3-6
3.2.8 Push-To-Talk (PTT) .......................................................................................................... 3-7
3.2.9 Hang-Up Button (HUB) ..................................................................................................... 3-7
3.2.10 Ignition Sense Circuitry ..................................................................................................... 3-7
3.2.11 Keypad Scan..................................................................................................................... 3-7
3.2.12 Vacuum Fluorescent (VF) Voltage Converter Circuitry..................................................... 3-7
3.2.13 Vacuum Fluorescent Display Driver IC ............................................................................. 3-8
3.2.14 Vacuum Fluorescent Display ............................................................................................ 3-8
3.2.15 Backlight LEDs.................................................................................................................. 3-8
3.3 W9 Control Head ........................................................................................................................... 3-8
3.3.1 Display .............................................................................................................................. 3-8
3.3.2 W9 Controls and Indicators............................................................................................... 3-9
3.3.3 Control Board.................................................................................................................... 3-9
3.3.3.1 Microprocessor ........................................................................................................ 3-9
3.3.3.2 Watchdog Timer....................................................................................................... 3-9
3.3.3.3 Bus Transceiver ..................................................................................................... 3-10
3.3.3.4 Vacuum Fluorescent Voltage Converter ................................................................ 3-10
3.3.3.5 Vehicle Interface Ports........................................................................................... 3-10
3.3.3.6 Power Supply......................................................................................................... 3-10
3.3.3.7 Ignition Sense Circuits ........................................................................................... 3-10
3.3.3.8 EEPROM Write-Protect Circuit .............................................................................. 3-11
3.3.4 Display Board.................................................................................................................. 3-11
3.3.4.1 VF Display.............................................................................................................. 3-11
3.3.4.2 VF Display Driver ................................................................................................... 3-11
3.3.4.3 Status LEDs ........................................................................................................... 3-11
3.3.4.4 Backlight LEDs....................................................................................................... 3-11
3.3.5 Default Jumper Settings.................................................................................................. 3-11
3.4 Vehicle Interface Port (VIP) ......................................................................................................... 3-12
3.4.1 W4, W5, and W7 Control Heads..................................................................................... 3-12
3.4.1.1 VIP Output Connections ........................................................................................ 3-12
3.4.1.1.1 Dash-Mount Installations ................................................................................ 3-12
3.4.1.1.2 Remote-Mount Installations ............................................................................ 3-13
3.4.1.2 VIP Input Connections (Remote-Mount Only)........................................................ 3-13
3.4.2 W9 Control Heads........................................................................................................... 3-14
3.4.2.1 VIP Output Connections ........................................................................................ 3-14
3.4.2.2 VIP Input Connections ........................................................................................... 3-14
Chapter 4 Test Equipment and Service Aids ..................................... 4-1
September 26, 2003
Table of Contents
6881096C77-O