Code Read Protection - Philips LPC2194 User Manual

Philips Semiconductors Preliminary User Manual
ARM-based Microcontroller LPC2119/2129/2194/2292/2294

CODE READ PROTECTION

This feature is available as of Bootloader revision 1.61.
Code read protection is enabled by programming the flash address location 0x1FC (User flash sector 0) with value 0x87654321
(2271560481 Decimal). Address 0x1FC is used to allow some room for the fiq exception handler. When the code read protection
is enabled the JTAG debug port, external memory boot and the following ISP commands are disabled:
• Read Memory
• Write to RAM
• Go
• Copy RAM to Flash
The ISP commands mentioned above terminate with return code CODE_READ_PROTECTION_ENABLED.
The ISP erase command only allows erasure of all user sectors when the code read protection is enabled. This limitation does
not exist if the code read protection is not enabled. IAP commands are not affected by the code read protection.
Flash Memory System and Programming 269 May 03, 2004