Datasheet

Section 17 Serial Communication Interface 3 (SCI3)
Rev. 1.50 Sep. 18, 2007 Page 377 of 584
REJ09B0240-0150
17.3.7 Serial Status Register (SSR)
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 Bit Name
Initial
Value R/W Description
7 TDRE 1 R/W Transmit Data Register Empty
Indicates whether TDR contains transmit data.
[Setting conditions]
• When the TE bit in SCR3 is 0
• When data is transferred from TDR to TSR
[Clearing conditions]
• When 0 is written to TDRE after reading TDRE = 1
• When the transmit data is written to TDR
6 RDRF 0 R/W Receive Data Register Full
Indicates that the received data is stored in RDR.
[Setting condition]
• When serial reception ends normally and receive
data is transferred from RSR to RDR
[Clearing conditions]
• When 0 is written to RDRF after reading RDRF = 1
• When data is read from RDR
5 OER 0 R/W Overrun Error
[Setting condition]
• When an overrun error occurs in reception
[Clearing condition]
• When 0 is written to OER after reading OER = 1