HD6433640 HITACHI [Hitachi Semiconductor], HD6433640 Datasheet - Page 335

• Manufacturer Part Number: HD6433640
• Description: H8/3644 Series Hardware Manual
• Manufacturer: HITACHI [Hitachi Semiconductor]

Data Transfer Operations
SCI3 Initialization: Data transfer on SCI3 first of all requires that SCI3 be initialized as described
in 10.3.4, SCI3 Initialization, and shown in figure 10.10.
Transmitting: Figure 10.16 shows an example of a flowchart for data transmission. This
procedure should be followed for data transmission after initializing SCI3.
1
2
Figure 10.16 Example of Data Transmission Flowchart (Synchronous Mode)
Clear bit TE to 0
Read bit TDRE
Read bit TEND
Continue data
Write transmit
transmission?
data to TDR
TDRE = 1?
TEND = 1?
in SCR3
in SSR
in SSR
Start
End
Yes
No
Yes
No
Yes
No
1.
2.
Read the serial status register (SSR) and
check that bit TDRE is set to 1, then write
transmit data to the transmit data register
(TDR). When data is written to TDR, bit
TDRE is cleared to 0 automatically, the
clock is output, and data transmission is
started.
When continuing data transmission, be
sure to read TDRE = 1 to confirm that
a write can be performed before writing
data to TDR. When data is written to
TDR, bit TDRE is cleared to 0 automatically.
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