h8s-2628 Renesas Electronics Corporation., h8s-2628 Datasheet - Page 356

• Manufacturer Part Number: h8s-2628
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 14 Serial Communication Interface (SCI)
14.3.7
SSR is a register containing status flags of the SCI and multiprocessor bits for transfer. 1 cannot
be written to flags TDRE, RDRF, ORER, PER, and FER; they can only be cleared. Some bit
functions of SSR differ between normal serial communication interface mode and Smart Card
interface mode.
Rev. 3.00 Oct 04, 2005 page 316 of 598
REJ09B0155-0300
Bit
7
6
Normal Serial Communication Interface Mode (When SMIF in SCMR Is 0)
Bit Name
TDRE
RDRF
Serial Status Register (SSR)
Initial Value
1
0
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]
The RDRF flag is not affected and retains their
previous values when the RE bit in SCR is cleared
to 0.
When the TE bit in SCR is 0
When data is transferred from TDR to TSR
and data can be written to TDR
When 0 is written to TDRE after reading TDRE
= 1
When the DTC is activated by a TXI interrupt
request and writes data 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 the DTC is activated by an RXI interrupt
and transferred data from RDR