Datasheet

Section 15 Serial Communication Interface with FIFO (SCIF)

Rev. 2.00 Aug. 20, 2008 Page 531 of 1198

REJ09B0403-0200

(2) Serial Data Transmission

Figure 15.4 shows an example of the data transmission flowchart.

Start transmission

Read THRE flag in FLSR

Write transmit data to FTHR

Read TEMT flag in FLSR

THRE = 1?

All data written

Yes

TEMT = 1

Yes

Break output

(End of transmission or transmission standby)

Yes

Break time completed

Initialization

Set BREAK bit in FLCR to 1

Clear BREAK bit in FLCR to 0

[1]

[2]

[3]

[1] Confirm that the THRE flag in FLSR is 1, and write transmit

data to FTHR. When FIFOs are used, write 1-byte to 16-byte

transmit data. When the OUT2 bit in FMCR and the ETBEI bit

in FIER are set to 1, an FTHR empty interrupt occurs. When

data is written to FTHR, it is transferred automatically to FTSR.

The data is then transmitted from the TxDF pin in the order of

the start bit, transmit data, parity bit, and stop bit.

[2] Read the TEMT flag in FLSR, and confirm that TEMT is set to

1 to ensure that all transmit data has been transmitted.

[3] To output a break at the end of serial transmission, set the

BREAK bit in FLCR to 1. After completion of the break time,

clear the BREAK bit in FLCR to 0 to clear the break.

Figure 15.4 Example of Data Transmission Flowchart