UTMR Output Modes

The UTMR module can generate either a pulsed or level output. When the OM bit in the TUxyCON0 register is set, the output will follow the Run/Stop state of the counter timer (level output), set to indicate that the timer is running, and cleared to indicate the timer has stopped. The output remains set through all Reset conditions, except when ERS is holding the timer/counter in a Reset state (RESET = ‘b11, level ERS Reset).

When the OM bit is cleared, the timer output is pulsed high at every period match (pulse output). The duration of the pulse is one single primary clock period at the end of the counter match period, regardless of the prescaler. This is demonstrated in Figure 3 and Figure 4 where the pulse output occurs only during the last timer clock period during the PR match.

The polarity of the output (pulsed or level) is controlled by the OPOL bit in the TUxyCON0 register. When OPOL is set, the output will either pulse low or be held low when timer output is active. When OPOL is cleared, the output will be either pulse high or be held high when timer output is active. The OPOL bit will control the output polarity of the module even when the module is disabled (ON = 0).
  1. 1.When START = ‘b01 or ‘b10 (edge-triggered), the level output is asserted as soon as the qualified ERS edge is registered without any synchronization delays (even when CSYNC = 1).
  2. 2.When LIMIT = 1, the pulse output will assert as indicated and will remain asserted until the counter changes from PR.
  3. 3.The OPOL bit does not affect the polarity of the RUN SFR bit.