UPD780973 Datasheet, PDF (222/301 Pages) NEC – 8-Bit Single-Chip Microcontrollers

CHAPTER 18 METER CONTROLLER/DRIVER
18.4.4 PWM output operation (output with 1 clock shifted)
Figure 18-8. Timing of Output with 1 Clock Shifted
Count clock
Meter 1 sin
(SM11, SM12)
Meter 1 cos
(SM13, SM14)
Meter 2 sin
(SM21, SM22)
Meter 2 cos
(SM23, SM24)
Meter 3 sin
(SM31, SM32)
Meter 3 cos
(SM33, SM34)
Meter 4 sin
(SM41, SM42)
Meter 4 cos
(SM43, SM44)
If the wave of sin and cos of meters 1 to 4 rises and falls internally as indicated by the broken line, the SM11
to SM44 pins always shift the count clock by 1 clock and output signals, in order to prevent VDD/GND from fluctuating.
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