In this tutorial we will see 8051 timers. We will use the 8051 timers to generate a precise delay of 1 sec.
8051 timers/counters
The 8051 has 2 timers/counters.
- They can be used to generate precise timing, i.e., we can measure time between events. The unit is then called timer.
- It can also be used to count external events, known as counter.
- Timer 1 is also used for generating baud rate in serial communication, which we will discuss in the next tutorial
Timer Counter Operation
| T0 | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| TH0 | TL0 | ||||||||||||||
| D15 | D14 | D13 | D12 | D11 | D10 | D9 | D8 | D7 | D6 | D5 | D4 | D3 | D2 | D1 | D0 |
| TMOD | |||||||
|---|---|---|---|---|---|---|---|
| D7 | D6 | D5 | D4 | D3 | D2 | D1 | D0 |
| Gate | C/T | M1 | M0 | Gate | C/T | M1 | M0 |
| Register | Operation |
|---|---|
| T0 | Timer 0 |
| T1 | Timer 1 |
| TCON | Timer Control |
| TMOD | Timer Mode |