Figure 17.18 Mode Transition Timing (Example: Boot Mode → User Mode ↔ User Program Mode) - Hitachi H8/3062 Hardware Manual

φ
t
OSC1
V
CC
FWE
MD to MD
2 0
RES
SWE set
SWE bit
Period during which flash memory access is prohibited
(x: Wait time after setting SWE bit)
Period during which flash memory can be programmed
(Execution of program in flash memory prohibited, and data reads other than verify operations prohibited)
Notes: *1 When entering boot mode or making a transition from boot mode to another mode, mode switching must be carried
out by means of RES input. The state of ports with multiplexed address functions and bus control output pins
(CSn, AS, RD, WR) will change during this switchover interval (the interval during which the RES pin input is low),
and therefore these pins should not be used as output signals during this time.
*2 When making a transition from boot mode to another mode, the mode programming setup time t
satisfied with respect to RES clearance timing.
See 22.2.6 Flash Memory Characteristics.
*3
(Example: Boot Mode → → → → User Mode ↔ ↔ ↔
Program-
ming/
Wait
erasing
time:
possible
x
Min 0µs
t
MDS
t
MDS
t
RESW
SWE
cleared
Boot
Mode Mode
*1
mode
change change
*3
Figure 17.18 Mode Transition Timing
Program-
ming/
Wait Wait
erasing
time: time:
possible
x
*2
t
MDS
User
User program mode
*1
mode
↔ User Program Mode)
Program-
ming/
Wait
erasing
time:
possible
x x
User
User program
mode mode
must be
MDS
Program-
ming/
erasing
possible
519