UPD78F9222MC(T)-5A4-A NEC, UPD78F9222MC(T)-5A4-A Datasheet - Page 67

• Manufacturer Part Number: UPD78F9222MC(T)-5A4-A
• Description: 8BIT MCU, 4K FLASH, 256B RAM, 78F9222
• Manufacturer: NEC

Specifications of UPD78F9222MC(T)-5A4-A

• Controller Family/series: UPD78
• No. Of I/o's: 17
• Ram Memory Size: 256Byte
• Cpu Speed: 10MHz
• No. Of Timers: 4
• No. Of: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 4KB
• Oscillator Type: External, Internal

4.4
4.4.1
(1) In output mode
(2) In input mode
4.4.2
(1) In output mode
(2) In input mode
4.4.3
(1) In output mode
(2) In input mode
The operation of a port differs, as follows, depending on the setting of the I/O mode.
Caution Although a 1-bit memory manipulation instruction manipulates 1 bit, it accesses a port in 8-bit
The data can be written to the output latch by a transfer instruction. In addition, the data of the output latch are
output from the pin. Once data is written to the output latch, it is retained until new data is written to the output
latch.
When a reset signal is generated, cleans the data in the output latch.
The data can be written to the output latch by a transfer instruction. Because the output buffer is off, however,
the pin status remains unchanged.
Once data is written to the output latch, it is retained until new data is written to the output latch.
When a reset signal is generated, cleans the data in the output latch.
The data of the output latch can be read by a transfer instruction. The data of the output latch remain unchanged.
The pin status can be read by a transfer instruction. The contents of the output latch remain unchanged.
An operation is performed on the data of the output latch. The result is written to the output latch. The data of the
output latch are output from the pin.
Once data is written to the output latch, it is retained until new data is written to the output latch.
When a reset signal is generated, cleans the data in the output latch.
The pin level is read and an operation is performed on its data. The operation result is written to the output latch.
However, the pin status remains unchanged because the output buffer is off.
When a reset signal is generated, cleans the data in the output latch.
Operation of Port Function
Writing to I/O port
Reading from I/O port
Operations on I/O port
units. Therefore, the contents of the output latch of a pin in the input mode, even if it is not
subject to manipulation by the instruction, are undefined in a port with a mixture of inputs and
outputs.
CHAPTER 4 PORT FUNCTIONS
User’s Manual U16898EJ5V0UD
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