Fujitsu MB90895 Series Hardware Manual page 623

Figure 19.8-2 Example of Sector Erasing Procedure
FFWR0/1
Accidental write preventive function setting
(Accidental write preventive sector: 0,
writing sector
1
Sector erase timer
(DQ3) 0
Internal address read
Erasing error
Start
FMCS: WE (bit5)
Programming enabled
Erase command sequence
(1) FFAAAA XXAA
(2) FF5554 XX55
(3) FFAAAA XX80
(4) FFAAAA XXAA
(5) FF5554 XX55
(6) Code input to erase sector (30
YES Is any other
erase sector?
NO
Internal address read 1
Internal address read 2
Toggle bit (DQ6)
Data 1 = Data 2
NO
0
Timing limit
(DQ5)
1
Internal address read
Internal address read
NO
Toggle bit (DQ6)
Data 1 = Data 2
YES
Last sector
YES
FMCS : WE (bit 5)
Programming enabled
Completed
CHAPTER 19 512 KBIT FLASH MEMORY
:1 )
)
H
Next sector
YES
NO
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