P89C660 Philips Semiconductors, P89C660 Datasheet - Page 74

• Manufacturer Part Number: P89C660
• Description: 80C51 8-bit Flash microcontroller family
• Manufacturer: Philips Semiconductors

1. Security bits are independent of each other. Full-chip erase may be performed regardless of the state of the security bits.
2. Any other combination of lockbits is undefined.
3. Setting LBx doesn’t prevent programming of unprogrammed bits.
Philips Semiconductors
Security
The security feature protects against software piracy and prevents the contents of the Flash from being read. The Security Lock bits are located
in Flash. The P89C660/662/664/668 has 3 programmable security lock bits that will provide different levels of protection for the on-chip code
and data (see Table 16).
Table 16.
NOTE:
2002 Oct 28
80C51 8-bit Flash microcontroller family
16KB/32KB/64KB ISP/IAP Flash with 512B/1KB/2KB/8KB RAM
Level
1
2
3
4
SECURITY LOCK BITS
LB1
0
1
1
1
LB2
0
0
1
1
1
LB3
0
0
0
1
MOVC instructions executed from external program memory are disabled from fetching
code bytes from internal memory.
Same as level 1, plus block erase is disabled. Erase or programming of the status byte or
boot vector is disabled.
Same as level 2, plus verify of code memory is disabled.
Same as level 3, plus external execution is disabled.
74
PROTECTION DESCRIPTION
PROTECTION DESCRIPTION
P89C660/P89C662/P89C664/
P89C668
Product data