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LIST OF ILLUSTRATIONS

1-1

Board Layout Showing Factory-Configured Settings .............................................................................. 1-3

1-2

Interrupt and Interrupt Channel Jumper, P3 ............................................................................................. 1-4

1-3

Pulling Down the Interrupt Request Line ................................................................................................ 1-4

1-4

Interrupt Source Select Jumper, P4 .......................................................................................................... 1-5

1-5

8254 Timer/Counter Clock Source Jumpers, P5 ...................................................................................... 1-5

1-6

8254 Timer/Counter Circuit Block Diagram ........................................................................................... 1-6

1-7

Base Address Switch, S1 .......................................................................................................................... 1-6

1-8

Port C Buffer Circuitry ............................................................................................................................. 1-8

1-9

Port B Pull-up/Pull-down Resistor Circuitry ........................................................................................... 1-9

1-10

Adding Pull-ups and Pull-downs to Some Digital I/O Lines ................................................................... 1-9

2-1

P2 and P6 I/O Connector Pin Assignments .............................................................................................. 2-4

3-1

DM5806 Block Diagram .......................................................................................................................... 3-3

4-1

8254 Timer/Counter Circuit Block Diagram ......................................................................................... 4-10