Philips Semiconductors

Preliminary data

P87LPC759

Low power, low price, low pin count (14 pin)

microcontroller with 1 kbyte OTP

2002 Mar 21

28

Security Bits

When neither of the security bits are programmed, the code in the

EPROM can be verified. When only security bit 1 is programmed, all

further programming of the EPROM is disabled. At that point, only

security bit 2 may still be programmed. When both security bits are

programmed, EPROM verify is also disabled.

Table 7. EPROM Security Bits

SB2

SB1

Protection Description

1

1

Both security bits unprogrammed. No program security features enabled. EPROM is programmable and verifiable.

1

0

Only security bit 1 programmed. Further EPROM programming is disabled. Security bit 2 may still be programmed.

0

1

Only security bit 2 programmed. This combination is not supported.

0

0

Both security bits programmed. All EPROM verification and programming are disabled.