M38203M4 Datasheet, PDF (147/344 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.3 Timer X and timer Y
sTimer Y operating mode bits (bit 4 and bit 5)
The timer Y operating mode bits select a op-
erating mode of the timer Y.
Table 2.3.3 shows the relation between the timer
Y operating mode bits and the operating modes.
For an explanation of each mode operation,
refer to the section pertaining to the explana-
tion of each operation.
Table 2.3.3 Relation between timer Y operating mode bits
and operating modes
b5 b4
Operation mode
0 0 Timer mode
0 1 Period measurement mode
1 0 Event counter mode
1 1 Pulse width HL continuously measurement mode
sCNTR1 active edge switch bit (bit 6)
The CNTR1 active edge switch bit has a function which selects an active edge of the CNTR1 interrupt
and functions for each mode.
In the pulse width HL continuously measurement mode, this bit is invalid.
qCNTR1 interrupt
When bit 6 is “0,” the falling edge ( ) is active.
When bit 6 is “1,” the rising edge ( ) is active.
In the pulse width HL continuously measurement mode, an interrupt request occurs at the both
edges regardless of the value of this bit.
qPeriod measurement mode
This bit selects the duration which is measured.
When bit 6 is “0,” the falling edge to the falling edge duration is measured.
When bit 6 is “1,” the rising edge to the rising edge duration is measured.
qEvent counter mode
An active edge of the count source is selected.
When bit 6 is “0,” the rising edge ( ) is active.
When bit 6 is “1,” the falling edge ( ) is active.
sTimer Y stop control bit (bit 7)
The timer Y stop control bit controls the count operation of the timer Y.
By writing “0” to bit 7, a count source is input to the Y counter, so that a count operation is started.
As bit 7 is in the “0” state immediately after reset release, the count operation is automatically started
after reset release.
By writing “1” to bit 7, the input of count source to the Y counter is stopped, so that the count operation
stops.
At read, this bit functions as a status bit to indicate the operating state (counting or stop) of the
counter. When bit 7 is “0,” the counter is in the operating state. When bit 7 is “1,” the counter is in
the stop state.
3820 GROUP USER’S MANUAL
2–61