Datasheet

Section 16 Serial Communication Interface (SCI, IrDA)
(The H8S/2695 is not equipped with an IrDA function)
Page 740 of 1434 R01UH0166EJ0600 Rev. 6.00
Mar 02, 2011
H8S/2633 Group, H8S/2633 F-ZTAT
TM
,
H8S/2633R F-ZTAT
TM
, H8S/2695
16.2.7 Serial Status Register (SSR)
7
TDRE
1
R/(W)*
6
RDRF
0
R/(W)*
5
ORER
0
R/(W)*
4
FER
0
R/(W)*
3
PER
0
R/(W)*
0
MPBT
0
R/W
2
TEND
1
R
1
MPB
0
R
Bit
Initial value
R/W
:
:
:
Note: * Only 0 can be written, to clear the flag.
SSR is an 8-bit register containing status flags that indicate the operating status of the SCI, and
multiprocessor bits.
SSR can be read or written to by the CPU at all times. However, 1 cannot be written to flags
TDRE, RDRF, ORER, PER, and FER. Also note that in order to clear these flags they must be
read as 1 beforehand. The TEND flag and MPB flag are read-only flags and cannot be modified.
SSR is initialized to H'84 by a reset, in standby mode, watch mode, subactive mode, and subsleep
mode or module stop mode.
Bit 7—Transmit Data Register Empty (TDRE): Indicates that data has been transferred from
TDR to TSR and the next serial data can be written to TDR.
Bit 7
TDRE Description
0 [Clearing conditions]
• When 0 is written to TDRE after reading TDRE = 1
• When the DMAC
*
or DTC
*
is activated by a TXI interrupt and writes data to TDR
1 [Setting conditions] (Initial value)
• When the TE bit in SCR is 0
• When data is transferred from TDR to TSR and data can be written to TDR
Note: * This function is not available in the H8S/2695.