Watkins-Johnson Company WJ-8718A/MFP Instruction Supplement page 12

CONTENTS
TABLE OF CONTENTS (Cont'd)
SECTIONlli
CIRCUIT DESCRIPTION (Cont'd)
WJ-8718A/MFP
Paragraph
3.1.3.9.2
3.1.3.9.3
3.1.3.10
3.1.3.11
3.1.3.12
3.1.3.13
3.1.3.14
3.1.3.15
3.1.3.16
3.2
3.2.1
3.2.2
3.2.3
3.2.3.1
3.2.3.1.1
3.2.3.1.2
3.2.3.1.3
3.2.3.2
3.2.3.3
3.2.3.4
3.2.3.5
3.2.4
3.2.4.1
3.2.4.2
3.2.4.3
3.2.4.3.1
3.2.4.3.2
3.2.4.3.3
3.2.4.3.4
3.2.4.4
3.2.4.4.1
3.2.4.4.2
3.2.4.4.3
3.2.4.4.4
3.2.4.4.5
3.2.4.4.6
3.2.4.4.7
3.2.4.5
3.2.4.6
3.2.4.7
vi
U2 Scan Line Outputs/Return Line Inputs ..•.•..•••....•••.••....••..•.•
U2 Output Ports BO Through B3 .......•........•....•.•...•...........
Column Driver (U12) •..................•........•.......•...........
Multiplexer (U8) ....•................................•.•............
Cathode Drivers (U9, U10) ...............•......•...........••....•..
Display Driver (U7) ..•................................•...•..•.......
Data Latch (U20) .........................................•.........
RF Gain/Meter Voltage Switch (U14) .............•.•..................
Tuning Wheel Register (U17) .
MFP Interface Circuit Descriptions ..........••........................
Memory Devices ...............................................•....
Read-Only/Wri te-Only Devices .
Microprocessor Theory .
Regis ters .............................•...............•...........•
Program Counter and Stack Pointer ......................•............
Instruction Register and Decoder ...............•......................
Arithmetic Logic Unit (AL U) and Flag Register .
Internal Clock Generator and Timing .
Interrupt Control ................•...........•..•....•.••...........
Data Bus Control Lines (RD, WR, ALE) ...................•......•.....
Reset In/Reset Out ......•.........•............••......••..•.....•.•
Type 794275-X Synthesizer Interface and Memory Board (MFP-A4) .
Microprocessor (U18) ...........•..•.......•••...•..•.••.............
Power Up/Down Circuit (U11) ...........•......•..•.....•...•.•...•..
Read-Only Memory (U1, U2) ..........•..•...•••.•.•.•.....•...•.......
EPROM Operation •.•.••.•..•.•..............•.•.•......••.........•
Control Inputs ...•....•.•.......•.....•..........•.••.•..•.•.........
Read Mode .
Standby Mode ........•.•..................•............•..•........
Random Access Memory (U3) ...••...•...•.....•...........•..........
RAM Operation .................•.....•................•............
Control Input ...•.....••......•.•.•..•...••••......•..•••.......•...
Read Mode ~ ' .
Write Mode _ .
High-Z Mode ...............•...•.•••......••.••••......•.•.....•...•
Low Power Mode .
Battery BackUp •..•.•..••...•......•.•......
~
..•.............••......
Bidirectional Bus Transceiver (U4) ................•••.....•............
Address Latch (U5, U6) •..••...•...........••..•.••......•••.........
Address Decoders (U7, U8) •.•.••..•.....•..••.........................
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