Datasheet

PIC18F6310/6410/8310/8410
DS39635C-page 144 2010 Microchip Technology Inc.
11.8 PORTH, LATH and
TRISH Registers
PORTH is an 8-bit wide, bidirectional I/O port. The cor-
responding Data Direction register is TRISH. Setting a
TRISH bit (= 1) will make the corresponding PORTH
pin an input (i.e., put the corresponding output driver in
a High-Impedance mode). Clearing a TRISH bit (= 0)
will make the corresponding PORTH pin an output (i.e.,
put the contents of the output latch on the selected pin).
The Output Latch register (LATH) is also memory
mapped. Read-modify-write operations on the LATH
register, read and write the latched output value for
PORTH.
All pins on PORTH are implemented with Schmitt
Trigger input buffers. Each pin is individually
configurable as an input or output.
When the external memory interface is enabled, four of
the PORTH pins function as the high-order address
lines for the interface. The address output from the
interface takes priority over other digital I/O. The
corresponding TRISH bits are also overridden.
EXAMPLE 11-8: INITIALIZING PORTH
Note: PORTH is only available on
PIC18F8310/8410 devices.
Note: On a Power-on Reset, these pins are
configured as digital inputs.
CLRF PORTH ; Initialize PORTH by
; clearing output
; data latches
CLRF LATH ; Alternate method
; to clear output
; data latches
MOVLW 0CFh ; Value used to
; initialize data
; direction
MOVWF TRISH ; Set RH3:RH0 as inputs
; RH5:RH4 as outputs
; RH7:RH6 as inputs