iii
LIST OF ILLUSTRATIONS
1-1
1-2
1-3
1-4
1-5
1-6
1-7
1-8
1-9
1-10
2-1
3-1
4-1
Board Layout Showing Factory-Configured Settings.............................................................................. 1-3
Interrupt and Interrupt Channel Jumper, P3............................................................................................. 1-4
Pulling Down the Interrupt Request Line ................................................................................................ 1-4
Interrupt Source Select Jumper, P4 .......................................................................................................... 1-5
8254 Timer/Counter Clock Source Jumpers, P5...................................................................................... 1-5
8254 Timer/Counter Circuit Block Diagram ........................................................................................... 1-6
Base Address Switch, S1.......................................................................................................................... 1-6
Port C Buffer Circuitry............................................................................................................................. 1-8
Port B Pull-up/Pull-down Resistor Circuitry ........................................................................................... 1-9
Adding Pull-ups and Pull-downs to Some Digital I/O Lines................................................................... 1-9
P2 and P6 I/O Connector Pin Assignments.............................................................................................. 2-4
DM5806 Block Diagram .......................................................................................................................... 3-3
8254 Timer/Counter Circuit Block Diagram ......................................................................................... 4-10