HD6433044 Datasheet, PDF (497/867 Pages) Hitachi Semiconductor – Hitachi Single-Chip Microcomputer

Figure 13-17 shows an example of SCI transmit operation.
Transmit
direction
Serial clock
Serial data
Bit 0 Bit 1
TDRE
TEND
TXI
request
TXI interrupt handler
writes data in TDR
and clears TDRE
flag to 0
1 frame
Bit 7 Bit 0 Bit 1
TXI
request
Bit 6 Bit 7
TEI
request
Figure 13-17 Example of SCI Transmit Operation
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