HD6417618 datasheet(407/646 Pages) RENESAS

407 / 646 page

Section 14 Serial Communication Interface with FIFO (SCIF)

Rev. 6.00 Jun. 12, 2007 Page 375 of 610

REJ09B0131-0600

14.4.3

Synchronous Mode

In synchronous mode, the SCIF transmits and receives data in synchronization with clock pulses.

This mode is suitable for high-speed serial communication.

The SCIF transmitter and receiver are independent, so full-duplex communication is possible

while sharing the same clock. The transmitter and receiver are also 16-byte FIFO buffered, so

continuous transmitting or receiving is possible by reading or writing data while transmitting or

receiving is in progress.

Figure 14.11 shows the general format in synchronous serial communication.

Don’t care

One unit of transfer data (character or frame)

Bit 0

Serial data

Synchronization

clock

Bit 1

Bit 3

Bit 4

Bit 5

LSB

MSB

Bit 2

Bit 6

Bit 7

Note: * High except in continuous transfer

Figure 14.11 Data Format in Synchronous Communication

In synchronous serial communication, each data bit is output on the communication line from one

falling edge of the serial clock to the next. Data is guaranteed valid at the rising edge of the serial

clock. In each character, the serial data bits are transmitted in order from the LSB (first) to the

MSB (last). After output of the MSB, the communication line remains in the state of the MSB. In

synchronous mode, the SCIF transmits data by synchronizing with the falling edge of the serial

clock, and receives data by synchronizing with the rising edge of the serial clock.

HD6417618 Datasheet(PDF) 407 Page - Renesas Technology Corp