PIC17C756A MICROCHIP [Microchip Technology], PIC17C756A Datasheet - Page 75

• Manufacturer Part Number: PIC17C756A
• Description: High-Performance 8-bit CMOS EPROM Microcontrollers with 10-bit A/D
• Manufacturer: MICROCHIP [Microchip Technology]

Example 10-2 shows an instruction sequence to initial-
ize PORTB. The Bank Select Register (BSR) must be
selected to Bank 0 for the port to be initialized. The fol-
lowing example uses the MOVLB instruction to load the
BSR register for bank selection.
FIGURE 10-6:
2000 Microchip Technology Inc.
Note: I/O pins have protection diodes to V
Weak
Pull-up
OE
BLOCK DIAGRAM OF RB3:RB2 PORT PINS
DD
and V
SS
Port
Input Latch
.
Port
Data
Q
EXAMPLE 10-2:
MOVLB
CLRF
MOVLW
MOVWF
CK
D
PORTB, F
0xCF
DDRB
0
Match Signal
from other
port pins
Q
; Init PORTB by clearing
;
; Value used to initialize
;
; Set RB<3:0> as inputs
;
;
; Select Bank 0
R
INITIALIZING PORTB
PIC17C7XX
output data latches
data direction
CK
RB<5:4> as outputs
RB<7:6> as inputs
D
RBPU
Peripheral Data In
DS30289B-page 75
Peripheral_enable
WR_PORTB (Q4)
Peripheral_output
RD_PORTB (Q2)
WR_DDRB (Q4)
RD_DDRB (Q2)
(PORTA<7>)
Data Bus
RBIF