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Section 21 Flash Memory
Rev. 1.00 Sep. 13, 2007 Page 909 of 1102
REJ09B0365-0100
21.14
Usage Notes
1. The initial state of the product at its shipment is in the erased state. For the product whose
revision of erasing is undefined, we recommend to execute automatic erasure for checking the
initial state (erased state) and compensating.
2. For the PROM programmer suitable for programmer mode in this LSI and its program version,
refer to the instruction manual of the socket adapter.
3. If the socket, socket adapter, or product index does not match the specifications, too much
current flows and the product may be damaged.
4. Use a PROM programmer that supports the device with 1-Mbyte on-chip flash memory and
3.3-V programming voltage. Use only the specified socket adapter.
5. Do not remove the chip from the PROM programmer nor input a reset signal during
programming/erasure in which a high voltage is applied to the flash memory. Doing so may
damage the flash memory permanently. If a reset is input accidentally, the reset must be
released after the reset input period of at least 100
s.
6. The flash memory is not accessible until FKEY is cleared after programming/erasure starts. If
the operating mode is changed and this LSI is restarted by a reset immediately after
programming/erasure has finished, secure the reset input period (period of
RES = 0) of at least
100
s. Transition to the reset state during programming/erasure is inhibited. If a reset is input
accidentally, the reset must be released after the reset input period of at least 100
s.
7. At powering on or off the Vcc power supply, fix the
RES pin to low and set the flash memory
to hardware protection state. This power on/off timing must also be satisfied at a power-off and
power-on caused by a power failure and other factors.
8. In on-board programming mode or programmer mode, programming of the 128-byte
programming-unit block must be performed only once. Perform programming in the state
where the programming-unit block is fully erased.
9. When the chip is to be reprogrammed with the programmer after execution of programming or
erasure in on-board programming mode, it is recommended that automatic programming is
performed after execution of automatic erasure.
10. To program the flash memory, the program data and program must be allocated to addresses
which are higher than those of the external interrupt vector table and H'FF must be written to
all the system reserved areas in the exception handling vector table.
11. The programming program that includes the initialization routine and the erasing program that
includes the initialization routine are each 4 Kbytes or less. Accordingly, when the CPU clock
frequency is 35 MHz, the download for each program takes approximately 60
s at the
maximum.