PIC24F04KA200 Datasheet, PDF(9/26 Page) Microchip Technology

English

English German Russian Spanish Italian Polish Chinese Japanese Korean French Portuguese	Language :

PIC24F04KA200 Datasheet, PDF (9/26 Pages) Microchip Technology – Flash Programming Specifications

◁

PIC24FXXKA2XX

3.5 Erasing Program Memory

To erase the program memory (all of code memory,

data memory and Configuration bits, including the

code-protect bits), set the NVMCON to 4064h and then

execute the programming cycle.

Figure 3-6 illustrates the ICSP programming process

for Bulk Erase. This process includes the ICSP

command code, which must be transmitted (for each

instruction), LSB first, using the PGCx and PGDx pins

(see Figure 3-2).

Table 3-4 provides the steps for executing serial

instruction for the Bulk Erase mode.

Note: Program memory must be erased before

writing any data to program memory.

FIGURE 3-6:

BULK ERASE FLOW

Start

Write 4064h to NVMCON SFR

Set the WR bit to Initiate Erase

Delay P11 + P10 Time

End

TABLE 3-4: SERIAL INSTRUCTION EXECUTION FOR CHIP ERASE

Command

(Binary)

Data

(Hex)

Description

Step 1: Exit the Reset vector.

0000

000000

040200

000000

NOP

GOTO

NOP

0x200

Step 2: Set the NVMCON to erase the entire program memory.

0000

24064A

883B0A

MOV #0x4064, W10

MOV W10, NVMCON

Step 3: Set the TBLPAG and perform dummy table write to select the erased memory.

0000

200000

880190

200000

BB0800

000000

MOV #<PAGEVAL>, W0

MOV W0, TBLPAG

MOV #0x0000, W0

TBLWTL W0, [W0]

NOP

Step 4: Initiate the erase cycle.

0000

A8E761

000000

BSET

NOP

NVMCON, #WR

Step 5: Repeat this step to poll the WR bit (bit 15 of NVMCON) until it is cleared by the hardware.

0000

0001

0000

000000

040200

000000

803B02

883C22

000000

<VISI>

000000

NOP

GOTO 0x200

NOP

MOV NVMCON, W2

MOV W2, VISI

NOP

Clock out the contents of the VISI register.

NOP

ï£ 2010 Microchip Technology Inc.

DS39991A-page 9

▷