upd78f0114hgb-8es-a Renesas Electronics Corporation., upd78f0114hgb-8es-a Datasheet - Page 85

• Manufacturer Part Number: upd78f0114hgb-8es-a
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

4.2.4 Port 3
using port mode register 3 (PM3). When used as an input port, use of an on-chip pull-up resistor can be specified by
pull-up resistor option register 3 (PU3).
Port 3 is a 4-bit I/O port with an output latch. Port 3 can be set to the input mode or output mode in 1-bit units
This port can also be used for external interrupt request input and timer I/O.
RESET input sets port 3 to input mode.
Figures 4-10 and 4-11 show block diagrams of port 3.
Caution In the PD78F0114HD, be sure to pull the P31 pin down after reset to prevent malfunction.
Remark P31/INTP2 and P32/INTP3 of the PD78F0114HD can be used as on-chip debug mode setting pins
PU3:
PM3:
RD:
WR
WR
WR
WR
RD
PORT
when the on-chip debug function is used.
FUNCTION ( PD78F0114HD ONLY).
PM
PU
: Write signal
Pull-up resistor option register 3
Port mode register 3
Read signal
PM30 to PM32
PU30 to PU32
(P30 to P32)
Output latch
Alternate
function
PU3
PM3
Figure 4-10. Block Diagram of P30 to P32
CHAPTER 4 PORT FUNCTIONS
User’s Manual U16961EJ4V0UD
For details, refer to CHAPTER 24 ON-CHIP DEBUG
EV
DD
P-ch
P30/INTP1 to
P32/INTP3
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