SH7144 Datasheet, PDF (429/773 Pages) Renesas Technology Corp – Hitachi SuperH RISC engine

Table 13.9 shows the states of the SSR status flags and receive data handling when a receive error
is detected. If a receive error is detected, the RDRF flag retains its state before receiving data.
Reception cannot be resumed while a receive error flag is set to 1. Accordingly, clear the OER,
FER, PER, and RDRF bits to 0 before resuming reception. Figure 13.9 shows a sample flow chart
for serial data reception.
Table 13.9 SSR Status Flags and Receive Data Handling
SSR Status Flag
RDRF* OER
1
1
0
0
0
0
1
1
1
1
0
0
1
1
FER
0
1
0
1
0
1
1
PER
0
0
1
0
1
1
1
Receive Data
Lost
Transferred to RDR
Transferred to RDR
Lost
Lost
Transferred to RDR
Lost
Note: * The RDRF flag retains its state before data reception.
Receive Error Type
Overrun error
Framing error
Parity error
Overrun error + framing error
Overrun error + parity error
Framing error + parity error
Overrun error + framing error +
parity error
Rev. 2.0, 09/02, page 389 of 732