Fujitsu FR81S 用户手册
CHAPTER 11: I/O PORTS
5. Operation
FUJITSU SEMICONDUCTOR LIMITED
CHAPTER : I/O PORTS
FUJITSU SEMICONDUCTOR CONFIDENTIAL
49
5.1.1. Peripheral I/O (bidirectional) Pin Assignment
The peripheral I/O (bidirectional) pin assignment is shown below.
Preparation
⋅
Since the pin once functions as a port as the result of step (1), also set the DDR and PDR values in
advance if necessary.
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For a pin with the AD converter function, set the applicable bit in the analog input enable register
(ADER) of the AD converter to "Port I/O mode". For information on the setting method, see
"CHAPTER: A/D CONVERTER".
(1)Set the PFR for the applicable pin to enable the port function.
(2)Disable the EPFRs for all other peripherals to be used by the relevant pin.
(3)If the relevant pin is also used for the external bus or the relevant peripheral is one of the targets of I/O
multiplexing, set the EPFR of the relevant peripheral. In addition, if the relevant peripheral has the I/O
relocation function, set the EPFR of the relevant peripheral.
(4)Set the PFR for the peripheral.
Figure 5-2 Peripheral I/O Assignment Procedure
EPFR
PFR
Peripheral
output value
External bus
Output value
Pin
Peripheral I/O
direction control
PDR
External bus I/O
direction control
DDR
To peripheral
input value
To input I/O relocation selection circuit
Input I/O relocation selection circuit
PDDR
EPFR
Input value from each pins
To peripheral input value
To external bus input value
(1)
(3)
(2)
(4)
(3)
MB91520 Series
MN705-00010-1v0-E
444