Section 13 Timer Z
To change duty cycles while a waveform with a duty cycle of 0% or 100% is being
output, make sure the following procedure.
•
•
To change duty cycles while a 0%-duty cycle waveform is being output, write to GR
while H'0000 ≤ TCNT_1 < previous GR value
To change duty cycles while a 100%-duty cycle waveform is being output, write to GR
while previous GR value< TCNT_0 ≤ GRA_0
Note that changing from a 0%-duty cycle waveform to a 100%-duty cycle waveform
and vice versa is not possible.
b. Buffer operation is used and TPSC2 = TPSC1 = TPSC0 = 0
Write H'0000 or a value equal to or more than the GRA_0 value to the buffer register.
•
•
To output a 0%-duty cycle waveform, write a value equal to or more than the GRA_0
value to the buffer register
To output a 100%-duty cycle waveform, write H'0000 to the buffer register
For details on buffer operation, see section 13.4.8, Buffer Operation.
c. Buffer operation is not used and other than TPSC2 = TPSC1 = TPSC0 = 0
Write a value which satisfies GRA_0 + 1 < GR < H'FFFF to GR directly at the timing
shown below.
•
•
To output a 0%-duty cycle waveform, write the value while H'0000 ≤ TCNT_1 <
previous GR value
To output a 100%-duty cycle waveform, write the value while previous GR value<
TCNT_0 ≤ GRA_0
To change duty cycles while a waveform with a duty cycle of 0% and 100% is being
output, the following procedure must be followed.
•
•
To change duty cycles while a 0%-duty cycle waveform is being output, write to GR
while H'0000 ≤ TCNT_1 < previous GR value
To change duty cycles while a 100%-duty cycle waveform is being output, write to GR
while previous GR value< TCNT_0 ≤ GRA_0
Note that changing from a 0%-duty cycle waveform to a 100%-duty cycle waveform
and vice versa is not possible.
d. Buffer operation is used and other than TPSC2 = TPSC1 = TPSC0 = 0
Write a value which satisfies GRA_0 + 1 < GR < H'FFFF to the buffer register. A
waveform with a duty cycle of 0% can be output. However, a waveform with a duty
cycle of 100% cannot be output using the buffer operation. Also, the buffer operation
cannot be used to change duty cycles while a waveform with a duty cycle of 100% is
being output. For details on buffer operation, see section 13.4.8, Buffer Operation.
Rev. 3.00 Sep. 10, 2007 Page 253 of 528
REJ09B0216-0300
RENESAS [ RENESAS TECHNOLOGY CORP ]
