UPD784938 Datasheet, PDF (183/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 6 PORT FUNCTIONS
6.10 Port 9
Port 9 is an 8-bit input/output port with an output latch. Input/output can be specified in 1-bit units by setting the port 9 mode
register (PM9). Each pin incorporates a software programmable pull-up resistor.
When RESET is input, port 9 is set as an input port (output high-impedance state), and the output latch contents are undefined.
6.10.1 Hardware configuration
The port 9 hardware configuration is shown in Figure 6-64.
Figure 6-64. Port 9 Block Diagram
WRPUOH
RDPUOH
Pull-up resistor option register H
PUOH9
WRPM9
Port 9 mode register
VDD
PM9n
RDPM9
Internal
bus
WRP9
RDP9
Output latch
P9n
P9n
n = 0 to 7
Preliminary User’s Manual U13987EJ1V0UM00
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