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CHAPTER 5 PORT FUNCTIONS
User’s Manual U12697EJ3V0UM
5.3 Control Registers
The following three types of registers control the ports.
• Port mode registers (PM0, PM2 to PM7, PM12, PM13)
• Pull-up resistor option registers (PU0, PU2, PU3, PU7, PU12, PUO)
• Port function control register 2 (PF2)
Note
Note
Applies only to the
µ
PD784225Y Subseries.
(1) Port mode registers (PM0, PM2 to PM7, PM12, PM13)
These registers are used to set port input/output in 1-bit units.
PM0, PM2 to PM7, PM12, and PM13 are set with a 1-bit or 8-bit memory manipulation instruction, respectively.
RESET input sets port mode registers to FFH.
When port pins are used as alternate function pins, set the port mode registers and output latches according to
Table 5-3.
Caution As port 0 has an alternate function as external interrupt request input, specifying the port
function output mode and changing the output level sets the interrupt request flag. When
the output mode is used, therefore, the interrupt mask flag should be preset to 1.
