Datasheet

Section 15 Serial Communication Interface (SCI)
Rev. 6.00 Mar. 18, 2010 Page 627 of 982
REJ09B0054-0600
TDRE clearance. To transmit with a different transmit mode after clearing the relevant mode,
the procedure must be started again from initialization. Figure 15.39 shows a sample flowchart
for mode transition during transmission. Port pin states are shown in figures 15.40 and 15.41.
Operation should also be stopped (by clearing TE, TIE, and TEIE to 0) before making a
transition from transmission by DTC transfer to module stop mode, software standby mode,
watch mode, subactive mode, or subsleep mode transition. To perform transmission with the
DTC after the relevant mode is cleared, setting TE and TIE to 1 will set the TXI flag and start
DTC transmission.
Read TEND flag in SSR
TE = 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]
[3]
[2]
TE = 1Initialization
<Start of transmission>
[1] 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
has been activated, the remaining
data in DTCRAM will be transmitted
when TE and TIE are set to 1.
[2] If TIE and TEIE are set to 1, clear
them to 0 in the same way.
[3] Includes module stop mode, watch
mode, subactive mode, and subsleep
mode.
Figure 15.39 Sample Flowchart for Mode Transition during Transmission