RX8804CE
Page - 28
ETM59E-05
When a “1” is written to the TE bit, the wakeup timer countdown starts from the preset value.
A wakeup timer interrupt
event starts a countdown based on the countdown period (source clock). When the count value
changes from 01h to 00h, an interrupt event occurs.
After the interrupt event occurs, the counter automatically reloads the preset value and again starts to count down.
(Repeated operation)
(3)
When a wakeup timer interrupt event occurs, “1” is written to the TF bit.
(4)
When the TF bit = “1” its value is retained until it is cleared to zero.
(5)
If the TIE bit = 1 when a wakeup timer interrupt occurs, /INT pin output goes low.
If the TIE bit = “0” when a wakeup timer interrupt occurs, /INT pin output remains Hi-Z.
(6)
Output from the /
INT pin remains low during the tRTN period following each event, after which it is automatically
cleared to Hi-Z status.
/INT is again set low when the next interrupt event occurs.
(7)
When a 0 is written to the TE bit, the wakeup timer function is stopped and the /INT pin is set to Hi-Z status.
When /INT
=
low, the wakeup timer function is stopped. The tRTN period is the maximum amount of time before the /INT
pin status changes from low to Hi-Z.
(8)
As long as /INT
=
low, the /INT pin status does not change when the TF bit value changes from “1”
to “0”.
(9)
When /INT
=
low, the /INT pin status changes from low to Hi-Z as soon as the TI
E bit value changes from “1” to
”0”.