UPD78F9502MA-CAC-A NEC, UPD78F9502MA-CAC-A Datasheet - Page 49

• Manufacturer Part Number: UPD78F9502MA-CAC-A
• Description: 8BIT MCU, 4K FLASH, 128B RAM, SMD
• Manufacturer: NEC

Specifications of UPD78F9502MA-CAC-A

• Controller Family/series: UPD78F
• No. Of I/o's: 8
• Ram Memory Size: 128Byte
• Cpu Speed: 10MHz
• No. Of Timers: 2
• No. Of Pwm: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 4KB
• Oscillator Type: External, Internal

4.2
4.2.1
port mode register 2 (PM2). When the P20 to P23 pins are used as an input port, an on-chip pull-up resistor can be
connected in 1-bit units by using pull-up resistor option register 2 (PU2).
therefore, depending on the selected system clock oscillator. The following two system clock oscillators can be used.
(1) High-speed internal oscillator
(2) External clock input
Control registers
Ports
Pull-up resistor
Ports consist of the following hardware units.
Port 2 is a 4-bit I/O port with an output latch. Each bit of this port can be set to the input or output mode by using
This port can also be used for timer I/O, and external interrupt request input.
The P23 pin is also used as the EXCLK pin of the system clock oscillator. The functions of the EXCLK pin differs,
The system clock oscillation is selected by the option byte. For details, refer to CHAPTER 13 OPTION BYTE.
Reset signal generation sets port 2 to the input mode.
Figures 4-2 to 4-4 show the block diagrams of port 2.
The P23 pin can be used as I/O port pin.
The P23 pin is used as the EXCLK pin to input an external clock, and therefore it cannot be used as an I/O port
pin.
Port Configuration
Port 2
Item
Port mode registers (PM2 to PM4)
Port registers (P2 to P4)
Pull-up resistor option registers (PU2 to PU4)
Total: 8 (CMOS I/O: 7, CMOS input: 1)
Total: 7
Table 4-2. Configuration of Ports
Preliminary User’s Manual U18681EJ1V0UD
CHAPTER 4 PORT FUNCTIONS
Configuration
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