Software Protection; Error Protection - Renesas H8S/2100 Series Hardware Manual

24.9.2

Software Protection

The software protection protects the flash memory against programming/erasing by disabling
download of the programming/erasing program and using the key code.
Table 24.15 Software Protection
Item Description
Protection The programming/erasing protection state is
by SCO bit entered when the SCO bit in FCCS is cleared to 0
to disable download of the programming/erasing
programs.
Protection The programming/erasing protection state is
by FKEY entered because download and
programming/erasing are disabled unless the
required key code is written in FKEY.
24.9.3

Error Protection

Error protection is a mechanism for aborting programming or erasure when a CPU runaway
occurs or operations not according to the programming/erasing procedures are detected during
programming/erasing of the flash memory. Aborting programming or erasure in such cases
prevents damage to the flash memory due to excessive programming or erasing.
If an error occurs during programming/erasing of the flash memory, the FLER bit in FCCS is set
to 1 and the error protection state is entered.
• When an interrupt request, such as NMI, occurs during programming/erasing.
• When the flash memory is read from during programming/erasing (including a vector read or
an instruction fetch).
• When a SLEEP instruction is executed (including software-standby mode) during
programming/erasing.
Section 24 Flash Memory
Function to be Protected
Programming/
Download Erasing
O O
O O
Rev. 1.00 Apr. 28, 2008 Page 799 of 994
REJ09B0452-0100