M32C8A Datasheet, PDF (360/372 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M32C/80 Series

M32C/8A Group
24. Usage Notes
24.7.2.3 Timer A (One-Shot Timer Mode)
• The TAiS bit (i = 0 to 4) in the TABSR register is set to 0 (count stops) after reset. Set the TAiS bit to 1
(count starts) after selecting timer operating mode and setting the TAi register.
• The following occurs when the TAiS bit in the TABSR register is set to 0 (count stops) while counting.
• The counter stops counting and the contents of the reload register is reloaded.
• The TAiOUT pin outputs a low-level (“L”) signal.
• The IR bit in the TAiIC register becomes 1 (interrupt requested) after one CPU clock cycle.
• One-shot timer is operated by an internal count source. When an external trigger is selected, a maximum of
one count source clock delay occurs between the trigger input to the TAiIN pin and the one-shot timer
output.
• The IR bit becomes 1 when one of the following procedures are used to set timer operating mode.
• When selecting one-shot timer mode after reset.
• When switching from timer mode to one-shot timer mode.
• When switching from event counter mode to one-shot timer mode.
To use the timer Ai interrupt (IR bit), set the IR bit to 0 after one of the above setting has done.
• When a retrigger occurs while counting, the contents of the reload register is reloaded after the counter
decrements by one, and continues counting.
To generate a retrigger while counting, wait 1 count source clock cycle or more after the last trigger.
• When an external trigger input is selected to start counting in timer A one-shot timer mode, do not provide
an external retrigger input for 300 ns before a timer A counter value reaches 0000h. One-shot timer may
stop counting.
(Technical update: TN-16C-125A/EA)
24.7.2.4 Timer A (Pulse Width Modulation Mode)
• The TAiS bit (i = 0 to 4) in the TABSR register is set to 0 (count stops) after reset. Set the TAiS bit to 1
(count starts) after selecting timer operating mode and setting the TAi register.
• The IR bit becomes 1 when one of the following procedures are used to select timer operating mode.
• When selecting PWM mode after reset.
• When switching from timer mode to PWM mode.
• When switching from event counter mode to PWM mode.
To use the timer Ai interrupt (IR bit), set the IR bit to 0 after one of the above setting has done.
• The following occurs when the TAiS bit is set to 0 (count stops) while PWM pulse is output.
• The counter stops.
• If the TAiOUT pin outputs a high-level (“H”) signal, the signal changes to “L” and the IR bit
becomes 1.
• If the TAiOUT pin outputs an “L” signal, its output signal and the IR bit remains unchanged.
Rev.1.00 Jul 15, 2007 Page 343 of 352
REJ09B0385-0100