Fujitsu FR81S User Manual
CHAPTER 40: MULTI-FUNCTION SERIAL INTERFACE
5. Operation of UART
FUJITSU SEMICONDUCTOR LIMITED
CHAPTER : MULTI-FUNCTION SERIAL INTERFACE
FUJITSU SEMICONDUCTOR CONFIDENTIAL
173
5.3.1.
Operation Mode 0 (One-to-One Connection)
In operation mode 0, asynchronous serial bidirectional communications can be performed.
CPU Interconnection
In operation mode 0 (normal mode), select bidirectional communications. Two CPUs are inter-connected as
shown in Figure 5-20:
Figure 5-20 Example of Connection for Bidirectional Communications
in UART Operation Mode 0
Flowchart
Figure 5-21 Example of Settings for Bidirectional Communications
FIFO Not Used
(Transmission side)
Start
Operation mode setting
(setting to mode0)
(setting to mode0)
Sets 1-byte data to
TDR for comunication
TDR for comunication
Reading and processing
of reception data
of reception data
RDRF=1
(Reception side)
Data transmission
Start
RDRF=1
Reading and processing
of reception data
of reception data
1-byte data
transmission
transmission
Yes
Yes
No
No
Data
transmission
(ANS)
Operation mode setting
(the same setting as
transmission side)
(the same setting as
transmission side)
SOT
SOT
SIN
SIN
SCK
SCK
CPU_1 (Master) CPU_2 (Slave)
MB91520 Series
MN705-00010-1v0-E
1486