UPD78F0988AGC-8BS Renesas Electronics America, UPD78F0988AGC-8BS Datasheet - Page 99

• Manufacturer Part Number: UPD78F0988AGC-8BS
• Manufacturer: Renesas Electronics America

Specifications of UPD78F0988AGC-8BS

• Lead Free Status / Rohs Status: Supplier Unconfirmed

4.4 Operation of Port Functions
4.4.1 Writing to I/O port
4.4.2 Reading from I/O port
4.4.3 Arithmetic operation of I/O port
The operation of a port differs depending on whether the port is set in the input or output mode, as described below.
(1) In output mode
(2) In input mode
(1) In output mode
(2) In input mode
(1) In output mode
(2) In input mode
A value can be written to the output latch of a port by using a transfer instruction. The contents of the output
latch can be output from the pins of the port.
Data once written to the output latch is retained until new data is written to the output latch.
A value can be written to the output latch by using a transfer instruction. However, the status of the port pin
is not changed because the output buffer is off.
Data once written to the output latch is retained until new data is written to the output latch.
Caution A 1-bit memory manipulation instruction is executed to manipulate 1 bit of a port. However,
The contents of the output latch can be read by using a transfer instruction. The contents of the output latch
are not changed.
The status of a pin can be read by using a transfer instruction. The contents of the output latch are not changed.
An arithmetic operation can be performed on the contents of the output latch. The result of the operation is
written to the output latch. The contents of the output latch are output from the port pins.
Data once written to the output latch is retained until new data is written to the output latch.
The contents of the output latch become undefined. However, the status of the pin is not changed because
the output buffer is off.
Caution A 1-bit memory manipulation instruction is executed to manipulate 1 bit of a port. However,
this instruction accesses the port in 8-bit units. When this instruction is executed to
manipulate a bit of an input/output port, therefore, the contents of the output latch of the pin
that is set in the input mode and not subject to manipulation become undefined.
this instruction accesses the port in 8-bit units. When this instruction is executed to
manipulate a bit of an input/output port, therefore, the contents of the output latch of the pin
that is set in the input mode and not subject to manipulation become undefined.
CHAPTER 4 PORT FUNCTIONS
User’s Manual U13029EJ7V1UD
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