4.2 One-Shot Mode
In TMR2, the One-Shot mode is identical to the Free-Running Period mode except that the
ON bit is cleared and the timer is stopped when T2TMR matches T2PR and will not restart
until the ON bit is cycled off and on. This can easily be achieved in UTMR using the
One-Shot Enable (OSEN) bit. The following table shows UTMR settings in different TMR2
One-Shot modes:
|
TMR2 MODE[4:0] | TMR2 Mode | UTMR Settings | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Output | Operation | Start | Reset | Stop | START | RESET | STOP | Other | |
01000 | One-shot | Software start | ON = 1 | — | ON = 0 (or) Next clock after PR
match | None (ON = 1) | At PR Match | At PR Match | OSEN = Enabled |
01001 |
Edge- Triggered Start | Rising edge start |
ON = (and) Rising ERS Edge | — | Rising ERS Edge | ||||
01010 | Falling edge start |
ON = (and) Falling ERS Edge | — | OSEN = Enabled (and) EPOL = Inverted | |||||
01011 | Any edge start |
ON = (and) Either ERS Edge | — | Either ERS Edge | At PR Match | OSEN = Enabled | |||
01100 |
Edge- Triggered Start and Hardware Reset |
Rising edge start and Rising edge Reset |
ON = (and) Rising ERS Edge | ERS = Rising ERS Edge | ON = 0 (or) Next clock after PR
match | Rising ERS Edge | At Start + PR Match | At PR Match | OSEN = Enabled |
01101 |
Falling edge start and Falling edge Reset |
ON = (and) Falling ERS Edge | ERS = Falling ERS Edge | At PR Match | OSEN = Enabled (and) EPOL = Inverted | ||||
01110 |
Rising edge start and Low-level Reset |
ON = (and) Rising ERS Edge | ERS = 0 | ERS Level - 0 + PR Match | OSEN = Enabled | ||||
01111 |
Falling edge start and High-level Reset |
ON = (and) Falling ERS Edge | ERS = 1 | OSEN = Enabled (and) EPOL = Inverted | |||||
10110 | Level Triggered Start and Hardware Reset | High-level start and Low-level Reset |
ON = | ERS = 0 | ON = 0 (or) Next clock after PR
match (or) Held in Reset | ERS Level - 1 | ERS Level - 0 + PR Match | At PR Match | OSEN = Enabled |
10111 |
Low-level start and High-level Reset |
ON = | ERS = 1 | OSEN = Enabled (and) EPOL = Inverted | |||||