Copy Microcontroller PIC16F630 Flash memory program and eeprom memory data to blank MCU PIC16F630 for a exact Microprocessor cloning;
PORTB is a 4-bit wide, bidirectional port. The corresponding data direction register is TRISB (Register 4-6). 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) when IC pic16lf677 program copying.
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) if mcu pic16f610 code extraction.
Example 4-3 shows how to initialize PORTB. Reading the PORTB register (Register 4-5) 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 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’. Each of the PORTB pins has an individually configurable internal weak pull-up when microcontroller pic12f635 firmware copying.
Control bits WPUB<7:4> enable or disable each pull-up (see Register 4-9). 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 RABPU bit of the OPTION register.
Four of the PORTB pins are individually configurable as an interrupt-on-change pin. Control bits IOCB<7:4> enable or disable the interrupt function for each pin. Refer to Register 4-10. The interrupt-on-change feature is disabled on a Power-on Reset after mcu pic12f675 code extraction.
For enabled interrupt-on-change pins, the present value is compared with the old value latched on the last read of PORTB to determine which bits have changed or mismatch the old value. The ‘mismatch’ outputs are OR’d together to set the PORTB Change Interrupt flag bit (RABIF) in the INTCON register.
