h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 662

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 21 ROM
21.9
All interrupts, including NMI input is disabled when flash memory is being programmed or erased
(when the P or E bit is set in FLMCR1), and while the boot program is executing in boot mode *
to give priority to the program or erase operation. There are three reasons for this:
1. Interrupt during programming or erasing might cause a violation of the programming or
2. In the interrupt exception handling sequence during programming or erasing, the vector would
3. If interrupt occurred during boot program execution, it would not be possible to execute the
For these reasons, in on-board programming mode alone there are conditions for disabling
interrupt, as an exception to the general rule. However, this provision does not guarantee normal
erasing and programming or MCU operation. All interrupt requests, including NMI input, must
therefore be disabled inside and outside the MCU when programming or erasing flash memory.
Interrupt is also disabled in the error-protection state while the P or E bit remains set in FLMCR1.
Notes: 1. Interrupt requests must be disabled inside and outside the MCU until the programming
Rev. 4.00 Jun 06, 2006 page 608 of 1004
REJ09B0301-0400
erasing algorithm, with the result that normal operation could not be assured.
not be read correctly *
normal boot mode sequence.
2. The vector may not be read correctly in this case for the following two reasons:
Interrupt Handling when Programming/Erasing Flash Memory
control program has completed programming.
•
•
If flash memory is read while being programmed or erased (while the P or E bit is
set in FLMCR1), correct read data will not be obtained (undetermined values will
be returned).
If the interrupt entry in the vector table has not been programmed yet, interrupt
exception handling will not be executed correctly.
(Mask ROM Version, H8S/2138 F-ZTAT, H8S/2134 F-ZTAT, and H8S/2132 F-ZTAT)
2
, possibly resulting in MCU runaway.
1
,