W55P241 Datasheet, PDF (16/32 Pages) List of Unclassifed Manufacturers – I/O device usable with many different microprocessors through SPI interface

W55P241
IO pads, PWMEN enables both internal ring oscillator and PWM output. Any bit of PWMEN can enable
the internal ring oscillator. In addition to PWMEN, the corresponding BP0D bit must be set to 1 to
generate PWM output. The duty ratio is determined by PWMn, where n = 0~7. When PWMn is larger
than or equal to the internal counter, the PWM output will be “1” if the corresponding BP0A and BP0B
bits are not equal. Therefore, PWM output must keep “1” for at least one PWM clock. The PWM output
will be made inverse if the corresponding BP0A and BP0B bits are equal. Note that except for power-
on reset, the internal PWM counter may not count from zero once it is enabled. Software reset
initializes the status of I/O (input, floating), not the PWM counter’s status. Note that in software reset,
bit6 of command byte must be 1 whatever the DIS pad status.
W^Wh^he^enⁿ t^th^he^e c^co^or^rr^re^es^sp^po^onⁿd^diⁱnⁿg^g b^biⁱt^ts^s o^of^fB^BU^PF⁰A^B and A^BT^PT⁰A are not equa^al^l
Counter
255 0 1 …........... 126 127 128 …........... 254 255 0
(1)
Comparator = 0
Output
(2)
Comparator = 127
Output
(3)
Comparator = 255
“1”
Output
“0”
Figure 9 Normal PWM output (B0x bit is not equal to A0x bit)
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