Hitachi H8S/2646 Hardware Manual page 499

Figure 13-6 shows an example of the operation for transmission in asynchronous mode.
Start
1 bit
0 D0
TDRE
TEND
TXI interrupt Data written to TDR and
request generated TDRE flag cleared to 0 in
TXI interrupt service routine
Figure 13-6 Example of Operation in Transmission in Asynchronous Mode
Data Parity
bit
D1 D7 0/1
TXI interrupt
request generated
1 frame
(Example with 8-Bit Data, Parity, One Stop Bit)
Stop Start
bit bit
1 0 D0 D1
Data Parity Stop
bit bit
D7 0/1 1
TEI interrupt
request generated
1
Idle state
(mark state)
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