UPD784026 Renesas Electronics Corporation., UPD784026 Datasheet - Page 127

• Manufacturer Part Number: UPD784026
• Description: 16/8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

5.2 PORT 0
bit-wise by means of the port 0 mode register (PM0). Each pin incorporates a software programmable pull-up resistor.
ports or one 8-bit real-time output port. The real-time output port control register (RTPC) is used to select whether this port is
used as a normal output port or a real-time output port.
5.2.1 Hardware Configuration
Port 0 is an 8-bit input/output port with an output latch, and has direct transistor drive capability. Input/output can be specified
P00 to P03 and P04 to P07 can output the buffer register (P0L, P0H) contents at any time interval as 4-bit real-time output
When RESET is input, port 0 is set as an input port (output high-impedance state), and the output latch contents are undefined.
The port 0 hardware configuration is shown in Figure 5-2.
Internal
Bus
WR
WR
RD
WR
WR
WR
RD
RD
RD
RTPC
RTPC
PUO
P0L
OUT
PM0
P0L
P0
P0
Port 0 Mode Register
Buffer Register
Pull-Up Resistor Option Register
Real-Time Output Port Control Register
(PM0m)
(P0HM)
(P0Hm)
PUO0
P0LM
PM0n
P0Ln
Figure 5-2 Port 0 Block Diagram
CHAPTER 5 PORT FUNCTIONS
Trigger
Selector
Output Latch
(P0m)
P0n
V
DD
P0n
(P0m)
n = 0, 1, 2, 3
m = 4, 5, 6, 7
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