BU21072MUV_16 Datasheet, PDF (13/40 Pages) Rohm – Capacitive Switch Controller ICs

BU21072MUV / BU21078MUV / BU21078FV
【0xE0-0xEB : Configuration of PWM】
Name:
PWM-0/1/2/3
Address: 0xE0 – 0xEB
Description: Each of the 4 PWM timers (PWM-0/1/2/3) has 5 parameters. One PWM timer is able to be assigned to one
LED port.
① RIS：Rising Period
If the setting value is 0x0, PWM function is disabled.
If the setting value is from 0x1 to 0xF, Rising Period is about 317[msec] x RIS.
(317 ≦ Rising Period ≦ 4755 [msec])
Update configuration timing：
In rising period：Within 3msec.
In other periods：Next rising period.
② FAL：Falling Period
If the setting value is 0x0, PWM function is disabled.
If the setting value is from 0x1 to 0xF, Falling Period is about 317[msec] x FAL.
(317 ≦ Falling Period ≦ 4755 [msec])
Update configuration timing：
In falling period：Within 3msec.
In other periods：Next falling period.
③ ON：Lighting-On Period
If the setting value is 0x0, LED always lights.
If the setting value is from 0x1 to 0xF, Light-On Period is about 300[msec] x ON.
(300 ≦ Lighting-On Period ≦ 4500 [msec])
In the case of that the LED always lights, the way to turn LED off is to write '0' to the LED port
register. And the interrupt of PWM continuous flashing of LED finish is not issued. Falling period
is applied.
Update configuration timing :
Next lighting-on period.
④ OFF：Lighting-Off Period
The settable range： 0x0 ≦ OFF ≦ 0xF
Light-Off Period is about 300[msec] x OFF.
(0 ≦ Lighting-Off Period ≦ 4500 [msec])
Update configuration timing :
Next lighting-off period.
⑤ REP：Repeat Count
If the setting value is 0x0, non repeat.
If the setting value is 0xF, unlimited repeat.
If the setting value is from 0x1 to 0xE, repeat as many times as the setting value.
When the PWM drive repeat as many times as the setting value, the register interrupt of PWM
continuous flashing is set to '1' and I/O port INT is set to "H". Interrupts are cleared by writing „0‟
to the register clear interrupt of PWM continuous flashing (Address 0xFB).
In the case that the setting is “unlimited repeat”, interrupts are not released.
Figure 9. PWM waveform
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TSZ02201-0L5L0F300640-1-2
14.Jul.2016 Rev.004