upd70f3422gj-gae-qs-ax Renesas Electronics Corporation., upd70f3422gj-gae-qs-ax Datasheet - Page 484

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

Chapter 14
484
Initial Value
Address
Access
Note
(4)
Reading the counter value via WTnCNT1 instead of WTnCNT0 is only
reasonable when the CPU clock is remarkably higher than WTCLK and the
overhead of multiple reading WTnCNT1 is justifiable.
WTnR - WTn reload register
The WTnR register is a dedicated register for setting the reload value of the
corresponding counter.
This register can be read/written in 16-bit units.
<base> + 4
0000
1.
2.
3.
4.
Preliminary User’s Manual U17566EE1V2UM00
15
WTnR can only be written when WTnCTL.WTCE = 1 (counter enabled).
The load value must be non-zero (0001
The contents of this register is automatically copied to the reload buffer.
The counters load their values from the respective buffers at underflow.
To ensure correct operation, this register shall not be written twice within
three cycles of the counter clock. A second write attempt within that time
span is ignored.
The value read from WTnR is the target start value. It is not necessarily
identical with the current start value that is stored in the reload buffer. The
buffer may not yet be updated.
H
14
. This register is cleared by any reset and when WTnCTL.WTCE = 0.
13
H
12
11
10
Down-counter load value
9
8
R/W
7
H
…FFFF
6
5
H
).
4
Watch Timer (WT)
3
2
1
0