85
CHAPTER 4 PORT FUNCTIONS
Preliminary User’s Manual U16035EJ1V0UM
4.3 Registers to Control Port Function
The following two types of registers control the ports.
•
Port mode registers (PM0, PM2 to PM5, PM7)
•
Pull-up resistor option registers (PU0, PU2 to PU5, PU7)
(1) Port mode registers (PM0, PM2 to PM5, PM7)
These registers are used to set port input/output in 1-bit units.
PM0, PM2 to PM5, and PM7 are independently set by a 1-bit or 8-bit memory manipulation instruction.
RESET input sets these registers to FFH.
Cautions 1. Pins P10 to P17 are input-only pins.
2. If a port has an alternate function pin and it is used as an alternate output function, set the
output latches (P0 and P2 to P7) to 0.