Epson S1C17001 Technical Manual page 148

D4 TRMD: Count Mode Select Bit
Selects the 8-bit timer count mode.
1 (R/W): One-shot mode
0 (R/W): Repeat mode (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 to run until stopped by the application. If the counter underflows, the timer presets the
counter to the reload data register value and continues the count. Thus, the timer periodically outputs an
underflow pulse. Set the 8-bit timer to this mode to generate periodic interrupts at desired intervals or to
generate a serial transfer clock.
Setting TRMD to 1 sets the 8-bit timer to One-shot mode. In this mode, the 8-bit timer stops automati-
cally as soon as the counter underflows. This means only one interrupt can be generated after the timer
starts. Note that the timer presets the counter to the reload data register value, then stops when an un-
derflow occurs. Set the 8-bit timer to this mode to set a specific wait time.
Note: Make sure the 8-bit timer count is halted before changing count mode settings.
D[3:2] Reserved
D1 PRESER: Timer Reset Bit
Resets the 8-bit timer.
1 (W): Reset
0 (W): Disabled
0 (R): Normally 0 when read out (default)
Writing 1 to this bit presets the counter to the reload data value.
D0 PRUN: Timer Run/Stop Control Bit
Controls the timer RUN/STOP.
1 (R/W): Run
0 (R/W): Stop (default)
The timer starts counting when PRUN is written as 1 and stops when written as 0. When the timer is
stopped, the counter data is retained until reset or until the next RUN state.
S1C17001 TECHNICAL MANUAL
EPSON
12 8-BIT TIMER (T8F)
139