Datasheet

608
18.3 Register Descriptions
18.3.1 Port A I/O Register H (PAIORH)
The port A I/O register H (PAIORH) is a 16-bit read/write register that selects input or output for
the most significant 8 pins of port A. Bits PA23IOR–PA16IOR correspond to pins PA23/WRHH
PA16/AH. PAIORH is enabled when the port A pins function as general input/outputs (PA23–
PA16). For other functions, it is disabled.
For port A pin functions PA23–PA16, a given pin in port A is an output pin if its corresponding
PAIORH bit is set to 1, and an input pin if the bit is cleared to 0.
PAIORH is initialized to H'0000 by external power-on reset; however, it is not initialized for
manual resets, reset by WDT, standby mode, or sleep mode, so the previous data is maintained.
The settings for this register are effective only for the 144-pin version. There are no corresponding
pins for this register in the 112-pin and 120-pin versions. However, read/writes are possible.
Bit: 15 14 13 12 11 10 9 8
———————
Initial value: 0 0 0 0 0 0 0 0
R/W: R R R R R R R R
Bit: 7 6 5 4 3 2 1 0
PA23
IOR
PA22
IOR
PA21
IOR
PA20
IOR
PA19
IOR
PA18
IOR
PA17
IOR
PA16
IOR
Initial value: 0 0 0 0 0 0 0 0
R/W: R/W R/W R/W R/W R/W R/W R/W R/W