Chapter 13 Real-Time Output Function (Rto); Function - NEC V850/SA1 mPD703015 Preliminary User's Manual

CHAPTER 13

13.1 Function

A function to transfer data set in advance to a real-time output buffer to an output latch by hardware to output the
data to an external device as soon as an external interrupt or external trigger have occurred is called a real-time
output function. The pins through which the data is output to an external device constitute a port called a real-time
output port.
Because RTO can output signals without jitter, it is suitable for controlling a stepping motor.
The real-time output port can be set in port mode or real-time output port mode in 1-bit units.
Figure 13-1 shows the block diagram of RTO.
RTPOE RTPEG
RTPTRG
Output trigger
INTTM4
control circuit
INTTM5
REAL-TIME OUTPUT FUNCTION (RTO)
Figure 13-1. Block Diagram of RTO
Internal bus
Real-time output port
control register (RTPC)
BYTE EXTR
4
Real-time output
buffer register,
high-order 4 bits
(RTBH)
Output latch
RTP7
Real-time output
buffer register,
low-order 4 bits
(RTBL)
RTP0
Real-time output
port mode register
(RTPM)
321