PIC16F883 Microchip Technology Inc., PIC16F883 Datasheet - Page 59

• Manufacturer Part Number: PIC16F883
• Description: 28/40/44-pin Flash-based, 8-bit Cmos Microcontrollers With Nanowatt Technology
• Manufacturer: Microchip Technology Inc.

3.6
PORTD
corresponding
(Register 3-12). Setting a TRISD bit (= 1) will make the
corresponding PORTD pin an input (i.e., put the
corresponding output driver in a High-Impedance mode).
Clearing a TRISD bit (= 0) will make the corresponding
PORTD pin an output (i.e., enable the output driver and
put the contents of the output latch on the selected pin).
Example 3-5 shows how to initialize PORTD.
Reading the PORTD register (Register 3-11) reads the
status of the pins, whereas writing to it will write to the
PORT latch. All write operations are read-modify-write
operations. Therefore, a write to a port implies that the
port pins are read, this value is modified and then written
to the PORT data latch.
REGISTER 3-11:
REGISTER 3-12:
© 2007 Microchip Technology Inc.
bit 7
Legend:
R = Readable bit
-n = Value at POR
bit 7-0
bit 7
Legend:
R = Readable bit
-n = Value at POR
bit 7-0
Note 1: PORTD is available on PIC16F884/887
TRISD7
R/W-1
R/W-x
RD7
(1)
PORTD and TRISD Registers
is a 8-bit wide, bidirectional port. The
only.
data
RD<7:0>: PORTD General Purpose I/O Pin bit
1 = Port pin is > V
0 = Port pin is < V
TRISD<7:0>: PORTD Tri-State Control bit
1 = PORTD pin configured as an input (tri-stated)
0 = PORTD pin configured as an output
TRISD6
R/W-1
R/W-x
RD6
PORTD: PORTD REGISTER
TRISD: PORTD TRI-STATE REGISTER
direction
W = Writable bit
‘1’ = Bit is set
W = Writable bit
‘1’ = Bit is set
TRISD5
register
IH
IL
R/W-1
R/W-x
RD5
is
PIC16F882/883/884/886/887
TRISD
TRISD4
R/W-1
R/W-x
RD4
Preliminary
U = Unimplemented bit, read as ‘0’
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
‘0’ = Bit is cleared
TRISD3
R/W-x
R/W-1
The TRISD register (Register 3-12) controls the PORTD
pin output drivers, even when they are being used as
analog inputs. The user should ensure the bits in the
TRISD register are maintained set when using them as
analog inputs. I/O pins configured as analog input always
read ‘0’.
EXAMPLE 3-5:
RD3
BANKSEL PORTD
CLRF
BANKSEL TRISD
MOVLW
MOVWF
PORTD
B‘00001100’
TRISD
TRISD2
R/W-x
R/W-1
RD2
INITIALIZING PORTD
;
;Init PORTD
;
;Set RD<3:2> as inputs
;and set RD<7:4,1:0>
;as outputs
x = Bit is unknown
x = Bit is unknown
TRISD1
R/W-x
R/W-1
RD1
DS41291D-page 57
TRISD0
R/W-1
R/W-x
RD0
bit 0
bit 0