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RL78/G1P
CHAPTER 6 TIMER ARRAY UNIT
R01UH0895EJ0100 Rev.1.00
164
Nov 29, 2019
6.5.3 Operation of counter
Here, the counter operation in each mode is explained.
(1) Operation of interval timer mode
<1> Operation is enabled (TEmn = 1) by writing 1 to the TSmn bit. Timer count register mn (TCRmn) holds the
initial value until count clock generation.
<2> A start trigger is generated at the first count clock after operation is enabled.
<3> When the MDmn0 bit is set to 1, INTTMmn is generated by the start trigger.
<4> By the first count clock after the operation enable, the value of timer data register mn (TDRmn) is loaded to
the TCRmn register and counting starts in the interval timer mode.
<5> When the TCRmn register counts down and its count value is 0000H, INTTMmn is generated and the value of
timer data register mn (TDRmn) is loaded to the TCRmn register and counting keeps on.
Figure 6-25. Operation Timing (In Interval Timer Mode)
Caution In the first cycle operation of count clock after writing the TSmn bit, an error at a maximum of one
clock is generated since count start delays until count clock has been generated. When the
information on count start timing is necessary, an interrupt can be generated at count start by
setting MDmn0 = 1.
Remark
f
MCK
, the start trigger detection signal, and INTTMmn become active between one clock
in
synchronization with f
CLK
.
f
MCK
(f
TCLK
)
m
TSmn (write)
TEmn
Start trigger
detection signal
TCRmn
Initial
value
m
TDRmn
INTTMmn
When MDmn0 = 1 setting
<1>
<3>
<4>
m
1
0000
m
0001
<2>
<5>