HD64F3670 RENESAS [Renesas Technology Corp], HD64F3670 Datasheet - Page 186

• Manufacturer Part Number: HD64F3670
• Description: Hitachi Single-Chip Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

13.3.7
SSR is a register containing status flags of the SCI3 and multiprocessor bits for transfer. 1 cannot
be written to flags TDRE, RDRF, OER, PER, and FER; they can only be cleared.
Bit
7
6
5
Rev. 2.0, 03/02, page 162 of 298
Bit Name
TDRE
RDRF
OER
Serial Status Register (SSR)
Initial Value
1
0
0
R/W
R/W
R/W
R/W
Description
Transmit Data Register Empty
Displays whether TDR contains transmit data.
[Setting conditions]
[Clearing conditions]
Receive Data Register Full
Indicates that the received data is stored in RDR.
[Setting condition]
[Clearing conditions]
Overrun Error
[Setting condition]
[Clearing condition]
When the TE bit in SCR3 is 0
When data is transferred from TDR to TSR
When 0 is written to TDRE after reading TDRE
= 1
When the transmit data is written to TDR
When serial reception ends normally and
receive data is transferred from RSR to RDR
When 0 is written to RDRF after reading RDRF
= 1
When data is read from RDR
When an overrun error occurs in reception
When 0 is written to OER after reading OER =
1