UPD30181 Datasheet, PDF (357/444 Pages) NEC – 64-/32-Bit Microprocessor

CHAPTER 18 LED CONTROL UNIT (LED)
18.2.4 LEDASTCREG (0x0B00 024A)
Bit
Name
R/W
RTCRST
Other resets
15
ASTC15
R/W
0
0
14
ASTC14
R/W
0
0
13
ASTC13
R/W
0
0
12
ASTC12
R/W
0
0
11
ASTC11
R/W
0
0
10
ASTC10
R/W
1
1
9
ASTC9
R/W
0
0
8
ASTC8
R/W
0
0
Bit
Name
R/W
RTCRST
Other resets
7
ASTC7
R/W
1
1
6
ASTC6
R/W
0
0
5
ASTC5
R/W
1
1
4
ASTC4
R/W
1
1
3
ASTC3
R/W
0
0
2
ASTC2
R/W
0
0
1
ASTC1
R/W
0
0
0
ASTC0
R/W
0
0
Bit
15 to 0
Name
ASTC(15:0)
LED auto stop time count
Function
This register is used to set the number of ON/OFF times prior to automatic stopping of LED blink. The set value is
read on a read. The initial setting is 1,200 times of ON/OFF pairs (i.e. one hour in which each time includes one
second of ON time and two seconds of OFF time).
The pair of operations in which the LED is switched ON once and OFF once is counted as “1” by this counter. The
counter counts down from the set value and an LEDINT interrupt request occurs when it reaches zero.
Caution Setting a zero to this register is prohibited. The operation is not guaranteed if zero is set to this
register.
User’s Manual U14272EJ3V0UM
357