h8s-2646 Renesas Electronics Corporation., h8s-2646 Datasheet - Page 756

• Manufacturer Part Number: h8s-2646
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 20 ROM
Rev. 5.00 Sep 22, 2005 page 730 of 1136
REJ09B0257-0500
Notes: 1. When entering boot mode or making a transition from boot mode to another mode, mode switching must be carried
V
FWE
MD2 to MD0
RES
SWE bit
CC
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)
2. When making a transition from boot mode to another mode, a mode programming setup time, t
3. See section 23.7, Flash Memory Characteristics.
out by means of RES input. The state of ports with multiplexed address functions and bus control output pins
(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.
is necessary with respect to the RES clearance timing.
(Example: Boot Mode → → → → User Mode ↔
t
OSC1
SWE set
Mode
change
t
MDS
t
MDS
*1
Figure 20.28 Mode Transition Timing
*3
Boot
mode
Mode
change
t
RESW
SWE
cleared
Min 0µs
t
MDS
*1
*2
User
mode
User program mode
↔ ↔
↔ User Program Mode)
User
mode
MDS
(min), of 200 ns
User program
mode