Renesas H8S/2318 series, Hardware Manual

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Rev. 5.00, 12/03, page 763 of 1088
V
CC
RES
Memory read mode
Command wait state
Command wait state
Normal/abnormal
end identification
Auto-program mode
Auto-erase mode
t
osc1
t
bmv
t
dwn
Command acceptance
Figure 17-95 Oscillation Stabilization Time, PROM Mode Setup Time, and
Power-Down Sequence
17.29.3 Procedure Program and Storable Area for Programming Data
In the descriptions in the previous section, the programming/erasing procedure programs and
storable areas for program data are assumed to be in the on-chip RAM. However, the program
and the data can be stored in and executed from other areas, such as part of flash memory which is
not to be programmed or erased, or somewhere in the external address space.
Conditions that Apply to Programming/Erasing
(1) The on-chip programming/erasing program is downloaded from the address set by FTDAR in
on-chip RAM, therefore, this area is not available for use.
(2) The on-chip programming/erasing program will use the 128 bytes as a stack. So, make sure
that this area is secured.
(3) Since download by setting the SCO bit to 1 will cause the MATs to be switched, it should be
executed in on-chip RAM.
(4) The flash memory is accessible until the start of programming or erasing, that is, until the
result of downloading has been judged. When in a mode in which the external address space is
not accessible, such as single-chip mode, the required procedure programs should be
transferred to the on-chip RAM before programming/erasing of the flash memory starts.
(5) The flash memory is not accessible during programming/erasing operations, therefore, the
operation program is downloaded to the on-chip RAM to be executed. The programs such as
that which activate the operation program, should thus be stored in on-chip memory other than
flash memory or the external address space.
(6) After programming/erasing, the flash memory should be inhibited until FKEY is cleared.
The reset state (RES = 0) must be in place for more than 100
µ
s when the LSI mode is changed
to reset on completion of a programming/erasing operation.
Transitions to the reset state, and hardware standby mode are inhibited during
programming/erasing. When the reset signal is accidentally input to the chip, a longer period
in the reset state than usual (100
µ
s) is needed before the reset signal is released.
(7) Switching of the MATs by FMATS should be needed when programming/erasing of the user
boot MAT is operated in user-boot mode. The program which switches the MATs should be