upd78f0124m6gba1-8et Renesas Electronics Corporation., upd78f0124m6gba1-8et Datasheet - Page 82

• Manufacturer Part Number: upd78f0124m6gba1-8et
• 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).
82
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
PU
PM
Pull-up resistor option register 0
Port mode register 0
Read signal
PM00, PM03
PU00, PU03
Output latch
(P00, P03)
Alternate
function
PM0
PU0
Figure 4-2. Block Diagram of P00 and P03
CHAPTER 4 PORT FUNCTIONS
User’s Manual U16315EJ3V1UD
EV
DD
P-ch
P00/TI000,
P03