Datasheet

PIC16F785/HV785

14.6 Data EEPROM Operation During

Code-Protect

Data memory can be code-protected by programming

the CPD bit in the Configuration Word (Register 15.2)

to ‘0’.

When the data memory is code-protected, the CPU is

able to read and write data to the data EEPROM. It is

recommended that the user code protect the program

memory when code protecting the data memory. This

prevents anyone from programming zeroes over the

existing code (which will execute as NOPs) to reach an

added routine, programmed in unused program mem-

ory, which outputs the contents of data memory.

Programming unused locations in program memory to

‘0’ will also help prevent data memory code protection

from becoming breached.

TABLE 14-1: REGISTERS/BITS ASSOCIATED WITH DATA EEPROM

Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

Value on

POR, BOR

Value on all

other Resets

EEADR EEADR7 EEADR6 EEADR5 EEADR4 EEADR3 EEADR2 EEADR1 EEADR0 0000 0000 0000 0000

EECON1

— — — — WRERR WREN WR RD ---- x000 ---- q000

EECON2 EEPROM Control register 2 (not a physical register) ---- ---- ---- ----

EEDAT EEDAT7 EEDAT6 EEDAT5 EEDAT4 EEDAT3 EEDAT2 EEDAT1 EEDAT0 0000 0000 0000 0000

INTCON GIE PEIE

T0IE INTE RAIE T0IF INTF RAIF 0000 0000 0000 0000

PIE1 EEIE

ADIE CCP1IE C2IE C1IE OSFIE TMR2IE TMR1IE 0000 0000 0000 0000

PIR1 EEIF

ADIF CCP1IF C2IF C1IF OSFIF TMR2IF TMR1IF 0000 0000 0000 0000

Legend: x = unknown, u = unchanged, – = unimplemented read as ‘0’, q = value depends upon condition. Shaded cells are not used by

data EEPROM module.