DSPIC33F datasheet(64/80 Pages) MICROCHIP

64 / 80 page

dsPIC33F/PIC24H PROGRAMMING SPECIFICATION

DS70152D-page 64

Preliminary

5.8

Reading Code Memory

Reading from code memory is performed by executing

a series of TBLRD instructions and clocking out the data

using the REGOUT command.

Table 5-9 shows the ICSP programming details for

reading code memory. In Step 1, the Reset vector is

exited. In Step 2, the 24-bit starting source address for

reading is loaded into the TBLPAG register and W6

is stored in TBLPAG and the lower 16 bits of the source

address are stored in W6.

To minimize the reading time, the packed instruction

word format that was utilized for writing is also used for

reading (see Figure 5-6). In Step 3, the write pointer,

W7, is initialized. In Step 4, two instruction words are

read from code memory and clocked out of the device,

through the VISI register, using the REGOUT command.

Step 4 is repeated until the desired amount of code

memory is read.

TABLE 5-9:

SERIAL INSTRUCTION EXECUTION FOR READING CODE MEMORY

Command

(Binary)

Data

(Hex)

Description

Step 1: Exit Reset vector.

0000

000000

040200

000000

NOP

GOTO

0x200

NOP

Step 2: Initialize TBLPAG and the read pointer (W6) for TBLRD instruction.

0000

200xx0

880190

2xxxx6

MOV

#<SourceAddress23:16>, W0

MOV

W0, TBLPAG

MOV

#<SourceAddress15:0>, W6

Step 3: Initialize the write pointer (W7) to point to the VISI register.

0000

207847

000000

MOV

#VISI, W7

NOP

Step 4: Read and clock out the contents of the next two locations of code memory, through the VISI register, using

the REGOUT command.

0000

0001

0000

0001

BA1B96

000000

<VISI>

BA9BB6

000000

<VISI>

TBLRDL [W6], [W7]

NOP

Clock out contents of VISI register

TBLRDH [W6++], [W7]

NOP

Clock out contents of VISI register

Step 5: Repeat step 4 until all desired code memory is read.

Step 6: Reset device internal PC.

0000

040200

000000

GOTO

0x200

NOP

DSPIC33F датащи(PDF) 64 Page - Microchip Technology

DSPIC33F датащи(HTML) 64 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

датащи скачать

ссылки URL