PIC17C752 datasheet(78/320 Pages) MICROCHIP

78 / 320 page

PIC17C75X

DS30264A-page 78

Preliminary

10.6 PORTF and DDRF Registers

PORTF is an 8-bit wide bi-directional port. The corre-

sponding data direction register is DDRF. A '1' in DDRF

conﬁgures the corresponding port pin as an input. A '0'

in the DDRF register conﬁgures the corresponding port

pin as an output. Reading PORTF reads the status of

the pins, whereas writing to them will write to the

respective port latch.

All eight bits of PORTF are multiplexed with 8 of the 12

channels of the 10-bit A/D converter.

Upon reset the entire Port is automatically conﬁgured

as analog inputs, and must be conﬁgured in software to

be a digital I/O.

Example 10-6 shows an instruction sequence to initial-

ize PORTF. The Bank Select Register (BSR) must be

selected to Bank 5 for the port to be initialized. The fol-

lowing example uses the MOVLB instruction to load the

BSR register for bank selection.

EXAMPLE 10-6: INITIALIZING PORTF

MOVLB

; Select Bank 5

MOVLW

0x0E

; Configure PORTF as

MOVPF

ADCON1 ; Digital

CLRF

PORTF

; Initialize PORTF data

;

latches before setting

;

the data direction

;

MOVLW

0x03

; Value used to initialize

;

data direction

MOVWF

DDRF

; Set RF<1:0> as inputs

;

RF<7:2> as outputs

FIGURE 10-13: BLOCK DIAGRAM OF RF7:RF0

Data bus

WR PORTF

WR DDRF

RD PORT

Data Latch

DDRF Latch

VSS

I/O pin

PCFG3:PCFG0

input

buffer

VDD

RD DDRF

To other pads

VAN

CHS3:CHS0

To other pads

PIC17C752 датащи(PDF) 78 Page - Microchip Technology

PIC17C752 датащи(HTML) 78 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

датащи скачать

ссылки URL