HD6437020 Datasheet, PDF (402/507 Pages) Hitachi Semiconductor – SuperH™ RISC engine

Initialize
(1)
Start transmitting
Read TDRE bit in SSR
(2)
TDRE = 1?
No
Yes
Write transmit data in TDR and
clear TDRE bit to 0 in SSR
All data transmitted?
Yes
Read TEND bit in SSR
No (3)
TEND = 1?
No
Yes
Clear TE bit SCR to 0
Transmission ends
Figure 13.17 Sample Flowchart for Serial Transmitting
Receiving Serial Data (clocked synchronous mode): Figure 13.18 shows a sample flowchart for
receiving serial data. When switching from the asynchronous mode to the clocked synchronous
mode, make sure that ORER, PER, and FER are cleared to 0. If PER or FER is set to 1, the RDRF
bit will not be set and both transmitting and receiving will be disabled. Figure 13.19 shows an
example of SCI recieve operation.
The procedure for recieving serial data is listed below.
1. SCI initialization: select the RxD pin function with the PFC.
2. Receive error handling: if a receive error occurs, read the ORER bit in SSR to identify the
error. After executing the necessary error handling, clear ORER to 0. Transmitting/receiving
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