UPD784915B Datasheet, PDF (32/86 Pages) NEC – 16-BIT SINGLE-CHIP MICROCONTROLLERS

µPD784915B, 784916B
RTP80 can output low-level, high-level, and high-impedance values real-time.
Because RTP80 can superimpose a horizontal sync signal, it can be used to create a pseudo vertical sync signal.
When RTP80 is set in the pseudo VSYNC output mode, it repeatedly outputs a specific pattern when an output trigger
occurs.
Figure 3-9 shows the operation timing of RTP80.
Figure 3-9. Example of Operation Timing of RTP80
(a) When HSYNC signal is superimposed
High level
P80 High impedance
Low level
Trigger signal
High level
P80 High impedance
Low level
Trigger signal
(b) Pseudo VSYNC output mode
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