IC Microchip

PORTB is an 8-bit wide bi-directional port. The corresponding
data direction register is TRISB. Setting a
TRISB bit (=1) will make the corresponding PORTB pin
an input, (i.e., put the corresponding output driver in a
hi-impedance mode). Clearing a TRISB bit (=0) will
make the corresponding PORTB pin an output, (i.e.,
put the contents of the output latch on the selected pin).
Each of the PORTB pins has a weak internal pull-up. A
single control bit can turn on all the pull-ups. This is performed
by clearing bit RBPU (OPTION_REG<7>). The
weak pull-up is automatically turned off when the port
pin is configured as an output. The pull-ups are disabled
on a Power-on Reset.
FIGURE 3-3: BLOCK DIAGRAM OF

IC Microchip

IC Microchip
Timer0: 8-bit timer/counter with 8-bit prescaler
Timer1: 16-bit timer/counter with prescaler,