8-Bit Timer Count Mode - Epson S1C17001 Technical Manual

12 8-BIT TIMER (T8F)

12.2 8-bit Timer Count Mode

The 8-bit timer features two count modes: Repeat mode and One-shot mode. These modes are selected using the
TRMD bit (D4/T8F_CTL register).
∗ TRMD: Count Mode Select Bit in the 8-bit Timer Control (T8F_CTL) Register (D4/0x4206)
Repeat mode (TRMD = 0, default)
Setting TRMD to 0 sets the 8-bit timer to Repeat mode.
In this mode, once the count starts, the 8-bit timer continues running until stopped by the application program.
If the counter underflows, the timer presets the reload data register value into the counter and continues the
count. Thus, the timer periodically outputs an underflow pulse. The 8-bit timer should be set to this mode to
generate periodic interrupts at desired intervals or to generate a serial transfer clock.
One-shot mode (TRMD = 1)
Setting TRMD to 1 sets the 8-bit timer to One-shot mode.
In this mode, the 8-bit timer stops automatically as soon as the counter underflows. This means only one inter-
rupt can be generated after the timer starts. Note that the timer presets the reload data register value to the coun-
ter, then stops after an underflow has occurred. The 8-bit timer should be set to this mode to set a specific wait
time.
Note: Make sure the 8-bit timer count is halted before changing count mode settings.
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S1C17001 TECHNICAL MANUAL