Panasonic F77G User Manual page 309

Chapter 8 Time Base Timer / 8-bit Free-running Timer
If the TM6CLRS flag of the TM6MD register is set to "0", TM6BC can be initialized in every
rewriting of TM6OC register, but in that state the timer 6 interrupt is disabled. If the timer 6
interrupt should be enabled, set the TM6CLRS flag to "1" after rewriting the TM6OC register.
On the timer 6 clock source selection, either the time base timer output or the time base
timer synchronous output is selected, the clock setup of time base timer is needed.
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8-bit Free-running Timer