HD6432345 Datasheet, PDF (614/907 Pages) Hitachi Semiconductor – H8S/2345 F-ZTAT Hardware Manual

17.13.9 Writer Mode Transition Time
Commands cannot be accepted during the oscillation stabilization period or the writer mode setup
period. After the writer mode setup time, a transition is made to memory read mode.
Table 17.31 Command Wait State Transition Time Specifications
Item
Standby release (oscillation
stabilization time)
Writer mode setup time
V_CC hold time
Symbol Min
t _osc1
10
t _bmv
10
t _dwn
0
Max Unit Notes
—
ms
—
ms
—
ms
VCC
RES
FWE
t_osc1
t_bmv
Memory read Auto-program mode
mode
Auto-erase mode
Command wait
state
t_dwn
Command
wait state
Normal/
abnormal end
identification
Don't care
Don't care
Note: Except in auto-program mode and auto-erase mode, drive the FWE input pin low.
Figure 17.34 Oscillation Stabilization Time, Writer Mode Setup Time, and Power Supply
Fall Sequence
17.13.10 Notes On Memory Programming
• When programming addresses which have previously been programmed, carry out auto-
erasing before auto-programming. (See figure 17.35.)
• When performing programming using writer mode on a chip that has been programmed/erased
in an on-board programming mode, auto-erasing is recommended before carrying out auto-
programming.
Notes: 1. The flash memory is initially in the erased state when the device is shipped by Hitachi.
For other chips for which the erasure history is unknown, it is recommended that auto-
erasing be executed to check and supplement the initialization (erase) level.
2. Auto-programming in the writer mode should be performed only once for each 128-
byte write unit block.
It is not possible to write additional data to a 128-byte write unit block that has already
been programmed. To reprogram a block, first use the auto-erase mode and then use
the auto-program mode.
602