upd70f3422gj-gae-qs-ax Renesas Electronics Corporation., upd70f3422gj-gae-qs-ax Datasheet - Page 479

• Manufacturer Part Number: upd70f3422gj-gae-qs-ax
• Description: 32-bit Single-chip Microcontroller
• Manufacturer: Renesas Electronics Corporation.

Watch Timer (WT)
Watch
Timer
Watch Calibration
Timer
WT0CTL.CE
WCTCLK
WTCLK
WT0CNT1
Figure 14-1
14.1.1 Description
WT0CNT0
INTWT0U
PRM00.ES00[1:0]
The following figure shows the structure of the Watch Timer and its connection
to the Watch Calibration Timer.
Watch Timer configuration
As shown in the figure, WT0 is clocked by WTCLK, a clock generated by the
Clock Generator. When WT0 counts down to zero, it generates the INTWT0UV
interrupt.
WT1 is clocked by the interrupts INTWT0UV. When WT1 reaches zero, it
generates the interrupt INTWT1UV.
Two control registers WTnCTL are used to enable the counters. This is done
by setting WTnCTL.WTCE to 1.
As soon as the counters are enabled, it is possible to write a start value to the
reload registers WT0R and WT1R.
WCT is a capture/compare timer. In this application, it measures the time
between two INTWT0UV interrupts. It is clocked by WCTCLK, another clock
generated by the Clock Generator.
Preliminary User’s Manual U17566EE1V2UM00
16-bit down-counter
detector
Edge
WT0
Reload buffer
WT0R
16-bit up-counter
Reload
CR000
TM00
Internal bus
Internal bus
WT1CTL.CE
on match
WT1CNT1
TMC00.TMC00[3:2]
WT1CNT0
16-bit down-counter
WT1
Reload buffer
WT1R
Reload
INTWT1U
(long interval)
INTWT0U
(short interval)
INTTM00
Chapter 14
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