UPD78F0034BGC-8BS-A Renesas Electronics America, UPD78F0034BGC-8BS-A Datasheet - Page 167

• Manufacturer Part Number: UPD78F0034BGC-8BS-A
• Description: MCU 8-Bit 78K0 CISC 32KB Flash 2.5V/3.3V/5V 64-Pin LQFP
• Manufacturer: Renesas Electronics America

Specifications of UPD78F0034BGC-8BS-A

• Package: 64LQFP
• Family Name: 78K0
• Maximum Speed: 12 MHz
• Ram Size: 1 KB
• Program Memory Size: 32 KB
• Operating Supply Voltage: 2.5|3.3|5 V
• Data Bus Width: 8 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 51
• Interface Type: 3-Wire/UART
• On-chip Adc: 8-chx10-bit
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 3

6.4 Port Function Operations
6.4.1 Writing to I/O port
(1) Output mode
(2) Input mode
6.4.2 Reading from I/O port
(1) Output mode
(2) Input mode
6.4.3 Operations on I/O port
(1) Output mode
(2) Input mode
Port operations differ depending on whether the input or output mode is set, as shown below.
Caution
A value is written to the output latch by a transfer instruction, and the output latch contents are output from the
pin.
Once data is written to the output latch, it is retained until data is written to the output latch again.
The output latch data is cleared by reset.
A value is written to the output latch by a transfer instruction, but since the output buffer is off, the pin status does
not change.
Once data is written to the output latch, it is retained until data is written to the output latch again.
The output latch contents are read by a transfer instruction. The output latch contents do not change.
The pin status is read by a transfer instruction. The output latch contents do not change.
An operation is performed on the output latch contents, and the result is written to the output latch. The output
latch contents are output from the pins.
Once data is written to the output latch, it is retained until data is written to the output latch again.
The output latch data is cleared by reset.
The output latch contents are undefined, but since the output buffer is off, the pin status does not change.
In the case of 1-bit memory manipulation instruction, although a single bit is manipulated, the
port is accessed as an 8-bit unit. Therefore, on a port with a mixture of input and output pins,
the output latch contents for pins specified as input are undefined, even for bits other than the
manipulated bit.
CHAPTER 6 PORT FUNCTIONS
User’s Manual U14046EJ5V0UD
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