HD6433636SW datasheet(247/418 Pages) RENESAS

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Bit 6—Receive Data Register Full (RDRF): Bit 6 is a status flag indicating whether there is

receive data in RDR.

Bit 6: RDRF

Description

Indicates there is no receive data in RDR

(initial value)

[Clearing conditions]

• After reading RDRF = 1, cleared by writing 0 to RDRF.

• When data is read from RDR by an instruction.

Indicates that there is receive data in RDR

[Setting condition]

When receiving ends normally, with receive data transferred from RSR to

RDR

Note:

If a receive error is detected during data receiving, or if bit RE in serial control register 3

(SCR3) is cleared to 0, RDR and RDRF are unaffected and keep their previous states. An

overrun error (OER) occurs if receiving of data is completed while bit RDRF remains set

to 1. If this happens, receive data will be lost.

Bit 5—Overrun Error (OER): Bit 5 is a status flag indicating that an overrun error has occurred

during data receiving.

Bit 5: OER

Description

Indicates that data receiving is in progress or has been completed*

(initial value)

[Clearing condition]

After reading OER = 1, cleared by writing 0 to OER

Indicates that an overrun error occurred in data receiving*

[Setting condition]

When data receiving is completed while RDRF is set to 1

Notes: 1. When bit RE in serial control register 3 (SCR3) is cleared to 0, OER is unaffected and

keeps its previous state.

2. RDR keeps the data received prior to the overrun; data received after that is lost. While

OER is set to 1, data receiving cannot be continued. In synchronous mode, data

transmitting cannot be continued either.

HD6433636SW Folha de dados(PDF) 247 Page - Renesas Technology Corp