h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 482

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 15 Serial Communication Interface (SCI, IrDA)
In serial reception, the SCI operates as described below.
1. The SCI monitors the transmission line, and if a 0 stop bit is detected, performs internal
2. The received data is stored in RSR in LSB-to-MSB order.
3. The parity bit and stop bit are received.
4. If the RIE bit in SCR is set to 1 when the RDRF flag changes to 1, a receive-data-full interrupt
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synchronization and starts reception.
After receiving these bits, the SCI carries out the following checks.
a. Parity check:
b. Stop bit check:
c. Status check:
If all the above checks are passed, the RDRF flag is set to 1, and the receive data is stored in
RDR.
If a receive error * is detected in the error check, the operation is as shown in table 15.11.
Note: * Subsequent receive operations cannot be performed when a receive error has
(RXI) request is generated.
Also, if the RIE bit in SCR is set to 1 when the ORER, PER, or FER flag changes to 1, a
receive-error interrupt (ERI) request is generated.
The SCI checks whether the number of 1 bits in the receive data agrees with the parity
(even or odd) set in the O/E bit in SMR.
The SCI checks whether the stop bit is 1.
If there are two stop bits, only the first is checked.
The SCI checks whether the RDRF flag is 0, indicating that the receive data can be
transferred from RSR to RDR.
occurred.
Also note that the RDRF flag is not set to 1 in reception, and so the error flags must
be cleared to 0.