HD6413003RF Datasheet, PDF (481/715 Pages) Renesas Technology Corp – Microcontroller (MCU)

Transmitting and Receiving Data
Transmitting Multiprocessor Serial Data: Figure 13-10 shows a sample flowchart for
transmitting multiprocessor serial data and indicates the procedure to follow.
Initialize
Start transmitting
Read TDRE flag in SSR
No
TDRE = 1?
Yes
Write transmit data in
TDR and set MPBT bit in SSR
Clear TDRE flag to 0
No
All data transmitted?
Yes
Read TEND flag in SSR
No
TEND = 1?
Yes
No
Output break signal?
Yes
Clear DR bit to 0, set DDR bit to 1
1 1. SCI initialization: the transmit data
output function of the TxD pin is
selected automatically.
2. SCI status check and transmit data
write: read SSR, check that the TDRE
2
flag is 1, then write transmit
data in TDR. Also set the MPBT flag to
0 or 1 in SSR. Finally, clear the TDRE
flag to 0.
3. To continue transmitting serial data:
after checking that the TDRE flag is 1,
indicating that data can be
written, write data in TDR, then clear
the TDRE flag to 0. When the DMAC
is activated by a transmit-data-empty
interrupt request (TXI) to write data in
TDR, the TDRE flag is checked and
cleared automatically.
4. To output a break signal at the end of
3
serial transmission: set the DDR bit to
1 and clear the DR bit to 0 (DDR and
DR are I/O port registers), then clear
the TE bit to 0 in SCR.
4
Clear TE bit to 0 in SCR
End
Figure 13-10 Sample Flowchart for Transmitting Multiprocessor Serial Data
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