2.68254 Timer/Counter
The 8254 Programmable timer/counter has 4 registers from Base+0 through Base+3. For detailed programming information about 8254, please refer to Intel‘s “Microsystem Components Handbook”. The block diagram is as below.
Gate |
Cin | Cout |
| Counter 0 |
Cin: clock input |
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| Counter 1 |
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Cout: clock output |
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INTCLK: internal clock |
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| Cin | Gate | Cout | ||||
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| Counter 2 |
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2M | Cin |
| Cout | |
INTCLK | Gate | |||
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PACER CLK
VCC
10K
Counter0, counter1 and counter2 are all 16 bit counters. Counter 1 and counter 2 cascade as a
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