Fujitsu MB90335 Series Hardware Manual page 444

MB90335 Series
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Communication procedure
Communications start at any timing from the transmitting side when transmit data is provided. On the
transmission side, load transmit data into the serial output data register 0, 1 (SODR0, SODR1) and set the
transmission enable bit (SCR0, SCR1:TXE) in the serial control register to "1" to start transmission.
Figure 18.7-7 shows the example of transferring the receiving data to the sender to indicate that the data
was successfully sent. Upon the receipt of the sending data, the receiver periodically returns ANS (1 byte in
this example).
Operation mode setting
(either of 0 or 2)
Set 1 byte data to SODR
and communicate.
Reception data is
NO
Receive data reading
and processing
CM44-10137-6E
Figure 18.7-7 Flowchart for Bidirectional Communication
(Sender)
START
Data transfer
existing.
YES
Data transfer
FUJITSU MICROELECTRONICS LIMITED
18.7 Explanation of Operation of UART
Operation mode setting
(tune to transfer side)
Reception data is
NO
Reception data read
1 byte data transfer
(ANS)
CHAPTER 18 UART
(Receiver)
START
existing.
YES
and process
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