upd70f3422gj-gae-qs-ax Renesas Electronics Corporation., upd70f3422gj-gae-qs-ax Datasheet - Page 851

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

Sound Generator (SG)
Note
(1)
To achieve 100 % duty cycle for all PWM frequencies, SGOFL must not be set
to a value above 1FE
The PWM signal is continually low when the value of the volume buffer is
zero—the sound has stopped.
Updating the volume buffer value
The value of the volume compare buffer can be changed by writing to the
volume register SG0PWM.
• If the register is cleared by writing 0000
• As a result, the sound stops at the latest after one period of SG0CLK.
• If a non-zero value is written to the register, the buffer is updated with the
Preliminary User’s Manual U17566EE1V2UM00
volume compare buffer with the next rising edge of SG0CLK.
next falling or rising edge of the tone frequency (match between SG0FH
counter value and SG0FH buffer value).
H
.
H
, the register value is copied to the
Chapter 24
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