PIC16F1938-I/ML Microchip Technology, PIC16F1938-I/ML Datasheet - Page 91

• Manufacturer Part Number: PIC16F1938-I/ML
• Description: IC MCU 8BIT FLASH 28QFN
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 16Fr

Specifications of PIC16F1938-I/ML

• Core Size: 8-Bit
• Program Memory Size: 28KB (16K x 14)
• Oscillator Type: Internal
• Core Processor: PIC
• Speed: 32MHz
• Connectivity: I²C, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 25
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 11x10b
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Controller Family/series: PIC16F
• No. Of I/o's: 25
• Eeprom Memory Size: 256Byte
• Ram Memory Size: 1024Byte
• Cpu Speed: 32MHz
• Package: 28QFN EP
• Device Core: PIC
• Family Name: PIC16
• Maximum Speed: 32 MHz
• Operating Supply Voltage: 2.5|3.3|5 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 25
• Interface Type: I2C/SPI/USART
• On-chip Adc: 11-chx10-bit
• Number Of Timers: 5
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

6.3
PORTB is an 8-bit wide, bidirectional port. The
corresponding
(Register 6-9). Setting a TRISB bit (= 1) will make the
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 6-2 shows how to initialize PORTB.
Reading the PORTB register (Register 6-6) 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.
The TRISB register (Register 6-9) controls the PORTB
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 6-2 shows how to initialize PORTB.
EXAMPLE 6-2:
© 2009 Microchip Technology Inc.
BANKSEL PORTB
CLRF
BANKSEL ANSELB
CLRF
BANKSEL TRISB
MOVLW
MOVWF
Note:
PORTB and TRISB Registers
PORTB
ANSELB
B’11110000’ ;Set RB<7:4> as inputs
TRISB
The ANSELB register must be initialized to
configure an analog channel as a digital
input. Pins configured as analog inputs will
read ‘0’.
data
INITIALIZING PORTB
direction
;
;Init PORTB
;Make RB<7:0> digital
;
;and RB<3:0> as outputs
;
register
is
TRISB
Preliminary
6.3.1
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 Register 6-8). Each weak
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
register.
6.3.2
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
Reset. Reference Section 7.0 “Interrupt-On-Change”
for more information.
PIC16F193X/LF193X
WEAK PULL-UPS
INTERRUPT-ON-CHANGE
DS41364C-page 91