upd78f0103hmca1-5a4-a Renesas Electronics Corporation., upd78f0103hmca1-5a4-a Datasheet - Page 66

• Manufacturer Part Number: upd78f0103hmca1-5a4-a
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

4.2.1 Port 0
using port mode register 0 (PM0). When the P00 to P03 pins are used as an input port, use of an on-chip pull-up
resistor can be specified in 1-bit units by pull-up resistor option register 0 (PU0).
66
Port 0 is a 4-bit I/O port with an output latch. Port 0 can be set to the input mode or output mode in 1-bit units
This port can also be used for timer I/O.
RESET input sets port 0 to input mode.
Figures 4-2 to 4-4 show block diagrams of port 0.
PU0:
PM0:
RD:
WR××: Write signal
WR
WR
WR
RD
PORT
PM
PU
Pull-up resistor option register 0
Port mode register 0
Read signal
Alternate function
Output latch
PM00
PU00
(P00)
PM0
PU0
Figure 4-2. Block Diagram of P00
CHAPTER 4 PORT FUNCTIONS
User’s Manual U16846EJ3V0UD
V
DD
P-ch
P00/TI000