RL78/G1P
CHAPTER 6 TIMER ARRAY UNIT
R01UH0895EJ0100 Rev.1.00
167
Nov 29, 2019
(4) Operation of one-count mode
<1> Operation is enabled (TEmn = 1) by writing 1 to the TSmn bit.
<2> Timer count register mn (TCRmn) holds the initial value until start trigger generation.
<3> Rising edge of the TImn input is detected.
<4> On start trigger detection, the value of timer data register mn (TDRmn) is loaded to the TCRmn register and
count starts.
<5> When the TCRmn register counts down and its count value is 0000H, INTTMmn is generated and the value of
the TCRmn register becomes FFFFH and counting stops
.
Figure 6-28. Operation Timing (In One-count Mode)
Remark
The above figure shows the timing when the noise filter is not in use. By making the noise filter on-state,
the edge detection becomes 2 f
MCK
cycles (it sums up to 3 to 4 cycles) later than the normal cycle of
TImn input. The error per one period occurs be the asynchronous between the period of the TImn input
and that of the count clock (f
MCK
).
f
MCK
(f
TCLK
)
TSmn (write)
TEmn
TImn input
<1>
<2>
Rising edge
Edge detection
<4>
TCRmn
Initial value
1
Start trigger
detection signal
<3>
m
0
FFFF
INTTMmn
Start trigger input wait status
<5>