3820_03 Datasheet, PDF (195/349 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.5 Serial I/O1
Transmit enable bit
Transmit buffer
empty flag
Write “1”
Write transmit data to transmit buffer register
Write next transmit data
Transmit shift
register shift
completion flag
Shift clock
TxD
D0 D1 D2 D3 D4 D5 D6 D7 D0 D1
Fig. 2.5.4 Transmit timing example in clock synchronous mode
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3820 GROUP USER’S MANUAL