Datasheet

Table Of Contents
Section 13 Serial Communication Interface
Page 466 of 846 REJ09B0140-0900 Rev. 9.00
Sep 16, 2010
H8S/2215 Group
Read TEND flag in SSR
TE = TIE = TEIE = 0
Transition to software
standby mode, etc.
Exit from software
standby mode, etc.
Change
operating mode?
No
All data
transmitted?
TEND = 1
Yes
Yes
Yes
<Transmission>
No
No
[1]
[2]
TE = 1Initialization
<Start of transmission>
Data being transmitted is interrupted.
After exiting software standby mode,
etc., normal CPU transmission is
possible by setting TE to 1, reading
SSR, writing TDR, and clearing
TDRE to 0, but note that if the DTC
*
or the DMAC has been activated, the
remaining data in DTCRAM will be
transmitted when TE and TIE are set
to 1.
Includes module stop mode.
[1]
[2]
Note: * The TDRE and RDRF flags are
automatically cleared by the DTC
when the DTC's DISEL bit is
cleared to 0 and the transfer
counter value is not 0.
Consequently, it is necessary to
use the CPU to clear the TDRE
and RDRF flags if DISEL is set to
1 or if the transfer counter value
is 0.
Figure 13.40 Sample Flowchart for Mode Transition during Transmission
SCK output pin
TE bit
TxD output pin
Port input/output High outputPort input/output High output Start Stop
Start of transmission
End of
transmission
Port input/output
SCI TxD output
Port
SCI TxD
output
Port
Transition
to software
standby
Exit from
software
standby
Figure 13.41 Port Pin State of Asynchronous Transmission Using Internal Clock