PIC16F1847-I/SO Microchip Technology, PIC16F1847-I/SO Datasheet - Page 126

• Manufacturer Part Number: PIC16F1847-I/SO
• Description: 14 KB Flash, 1K Bytes RAM, 32 MHz Int. Osc, 16 I/0, Enhanced Mid Range Core 18 S
• Manufacturer: Microchip Technology

Specifications of PIC16F1847-I/SO

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PIC16(L)F1847
12.3
PORTB is an 8-bit wide, bidirectional port. The
corresponding
(Register
corresponding PORTB pin an input (i.e., put the
corresponding output driver in a High-Impedance mode).
Clearing a TRISB bit (= 0) will make the corresponding
PORTB pin an output (i.e., enable the output driver and
put the contents of the output latch on the selected pin).
Example 12-2
Reading the PORTB register
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.
The TRISB register
pin output drivers, even when they are being used as
analog inputs. The user should ensure the bits in the
TRISB register are maintained set when using them as
analog inputs. I/O pins configured as analog input always
read ‘0’.
EXAMPLE 12-2:
12.3.1
All of the PORTB pins are individually configurable as
an interrupt-on-change pin. Control bits IOCB<7:0>
enable or disable the interrupt function for each pin.
The interrupt-on-change feature is disabled on a
Power-on
“Interrupt-On-Change”
12.3.2
Each of the PORTB pins has an individually configurable
internal weak pull-up. Control bits WPUB<7:0> enable or
disable each pull-up (see
pull-up is automatically turned off when the port pin is
configured as an output. All pull-ups are disabled on a
Power-on Reset by the WPUEN bit of the OPTION_REG
register.
DS41453A-page 126
BANKSEL PORTB
CLRF
BANKSEL ANSELB
CLRF
BANKSEL TRISB
MOVLW
MOVWF
Example 12-2
PORTB and TRISB Registers
12-9). Setting a TRISB bit (= 1) will make the
PORTB
ANSELB
B’11110000’ ;Set RB<7:4> as inputs
TRISB
INTERRUPT-ON-CHANGE
WEAK PULL-UPS
shows how to initialize PORTB.
Reset.
data
(Register
shows how to initialize PORTB.
INITIALIZING PORTB
direction
;
;Init PORTB
;Make RB<7:0> digital
;
;and RB<3:0> as outputs
;
for more information.
Reference
Register
12-9) controls the PORTB
(Register
register
12-11). Each weak
12-8) reads the
Section 13.0
is
TRISB
Preliminary
12.3.3
The ANSELB register
configure the Input mode of an I/O pin to analog.
Setting the appropriate ANSELB bit high will cause all
digital reads on the pin to be read as ‘0’ and allow
analog functions on the pin to operate correctly.
The state of the ANSELB bits has no affect on digital
output functions. A pin with TRIS clear and ANSELB set
will still operate as a digital output, but the Input mode
will be analog. This can cause unexpected behavior
when executing read-modify-write instructions on the
affected port.
The TRISB register
pin output drivers, even when they are being used as
analog inputs. The user should ensure the bits in the
TRISB register are maintained set when using them as
analog inputs. I/O pins configured as analog input always
read ‘0’.
Note:
ANSELB REGISTER
The ANSELB register must be initialized
to configure an analog channel as a digital
input. Pins configured as analog inputs
will read ‘0’.
(Register
 2011 Microchip Technology Inc.
(Register
12-9) controls the PORTB
12-12) is used to