
7540 Group User’s Manual
APPLICATION
2-81
2.5 Timer Y and timer Z
Fig. 2.5.25 Setting method for programmable waveform generation mode (2)
b7b0
0
1
b7b0
1
b7b0
0
Process 7: In order not to execute the no requested interrupt processing,
set “0” (no requested) to the timer Y interrupt request bit.
Interrupt request register 2 (IREQ2) [Address 3D16]
Process 8: When Timer Y interrupt is used, set “1” (interrupt enabled)
to the timer Y interrupt enable bit.
No timer Y interrupt request issued
Interrupt control register 2 (ICON2) [Address 3F16]
Timer Y interrupt enabled
Timer Y, Z mode register (TYZM) [Address 2016]
Timer Y count start
Process 9: Start counting of timer Y.
b7b0
0
Notes 1: For Timer Z, f(XIN)/16, f(XIN)/2, or timer Y underflow can be selected.
However, when the timer Z waveform expansion function is used,
do not select the timer Y underflow for the timer Z count source.
2: Set the ring oscillator oscillation to be enabled by bit 3 (ring oscillator
oscillation control bit) of CPU mode register.
Process 6: Set the count value to timer Y (Note 1).
 Set the count value to prescaler Y, timer Y secondary and timer Y primary
Count value
Timer Y secondary (TYS) (Address 2216)
Count value
Process 5: Set timer Y count source (Note 1).
Timer count source set register (TCSS) [Address 2E16]
Timer Y count source selection bits
b3 b2
0 0 : f(XIN)/16
0 1 : f(XIN)/2
1 0 : Ring oscillator output (Note 2)
1 1 : Not available
Prescaler Y (PREY) (Address 2116) (Note 2)
Timer Y primary (TYP) (Address 2316) (Notes 3, 4)
Count value
Notes 1: In the programmable waveform generation mode, values of TYS,
EXPYP, and EXPYS are valid by writing to TYP. Even when
changing TYP is not required, write the same value again.
2: When the timer Y waveform extension function is used, be sure to set
“0016” to prescaler Y.
3: In the programmable waveform generation mode, when the setting
value is changed while the waveform is output, set by software in
order not to execute the writing to TYP and the timing of timer Y
underflow during the secondary interval simultanesously.
4: Count values of the primary interval and secondary interval can be
checked by reading the TYP (TYS is undefined at read).