CHAPTER 18 LED CONTROL UNIT (LED)
User’s Manual U14272EJ3V0UM
359
18.3 Operation Flow
Set LEDHTSREG
Set LEDLTSREG
LEDCNTREG
LEDSTOP = 1
Set LEDASTCREG
LEDCNTREG
LEDENABLE = 1
LED blinking time setting
• LEDHTSREG
Set LED ON time.
• LEDLTSREG
Set LED OFF time.
• LEDASTCREG
Set number of LEDs blinking.
LED auto stop setting
• LEDSTOP
Set this bit to enable the LED blink auto stop function.
This setting terminates LED blinking automatically after
blinking time set above has elapaed.
LED blinking operation start
• LEDENABLE
Set this bit to start LED blinking operation.
Caution
Setting these registers to 0 is prohibited because it may
cause undefined operation.
LED blinking operation
• Supervising the auto stop counter
LED blinking terminates when the auto stop counter reaches 0.
LED blinking operation termination
• LEDENABLE
LED blinking operation is terminated by setting 0 to this bit.
LED blinking operation terminate interrupt request generation
• LEDINT
An interrupt request to the ICU is generated when 1 is set to
this bit.
Caution
Setting the LEDENABLE and LEDSTOP bits to 0 is prohibited
because it may cause undefined operation.
Yes
No
LEDENABLE = 0
LEDSTOP = 0
LEDINT = 1
Register initial setting
• LEDHTSREG:
0x0010 (LED ON time available)
• LEDLTSREG:
0x0020 (LED OFF time available)
• LEDCNTREG:
0x0002
• LEDASTCREG:
0x04B0
LEDs blinking
operation
start condition
LEDs blink
Register
initial setting
Note
Auto stop
counter = 0
LEDs OFF
Software
End
Start
Hardware
Note Initial setting for each register must be performed when a power is supplied to device for the first time,
regardless whether LEDs blinking function is used or not.