NEC PD78212, User Manual

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CHAPTER 6 REAL-TIME OUTPUT FUNCTION
6.1 CONFIGURATION AND FUNCTION
The real-time output function is implemented by the hardware centering around port 0 and the buffer register (P0H
and P0L) as shown in Fig. 6-1.
The term real-time output function refers to a function that transfers data in the buffer register to the output latch
by hardware for output to the outside simultaneously when a timer interrupt or external interrupt occurs. The term
real-time output port refers to a pin used to output such data to the outside.
The real-time output function handles the following two types of real-time output data:
• 4 bits
×
2 channels
• 8 bits
×
1 channel
Combined use of the real-time output function and the macro service function (described later) implements a
pattern generator function with programmable timing without intervention by software.
The pattern generator function is suitable to control stepper motors.