PIC16F1507-ESLASHSS. datasheet(14/278 Pages) MICROCHIP

14 / 278 page

PIC16(L)F1507

DS40001586D-page 14

 2011-2015 Microchip Technology Inc.

FIGURE 3-1:

PROGRAM MEMORY MAP

AND STACK FOR

PIC16(L)F1507

3.2.1

READING PROGRAM MEMORY AS

DATA

There are two methods of accessing constants in

program memory. The first method is to use tables of

RETLW

instructions. The second method is to set an

FSR to point to the program memory.

3.2.1.1

RETLW

Instruction

The RETLW instruction can be used to provide access

to tables of constants. The recommended way to create

such a table is shown in Example 3-1.

EXAMPLE 3-1:

RETLW

INSTRUCTION

The BRW instruction makes this type of table very

simple to implement. If your code must remain portable

with previous generations of microcontrollers, then the

BRW

instruction is not available so the older table read

method must be used.

Stack Level 0

Stack Level 15

Stack Level 1

Reset Vector

PC<14:0>

Interrupt Vector

Page 0

Rollover to Page 0

0000h

0004h

0005h

07FFh

0800h

7FFFh

CALL, CALLW

RETURN, RETLW

Interrupt,

RETFIE

On-chip

Program

Memory

Rev. 10-000040C

7/30/2013

constants

BRW

;Add Index in W to

;program counter to

;select data

RETLW DATA0

;Index0 data

RETLW DATA1

;Index1 data

RETLW DATA2

RETLW DATA3

my_function

;… LOTS OF CODE…

MOVLW

DATA_INDEX

call constants

;… THE CONSTANT IS IN W

PIC16F1507-E/SS. bảng dữ liệu(PDF) 14 Page - Microchip Technology

PIC16F1507-E/SS. bảng dữ liệu(HTML) 14 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

bảng dữ liệu tải về

Link URL