Fujitsu FR81S User Manual
CHAPTER 45: FLASH MEMORY
5. Operation
FUJITSU SEMICONDUCTOR LIMITED
CHAPTER : FLASH MEMORY
FUJITSU SEMICONDUCTOR CONFIDENTIAL
30
5.3.1. Command Sequence
The command sequence is shown below.
The automatic algorithm starts when half-word (16-bit) data is written to the flash memory once to six times
in a row. This is called a command. The command sequences are shown below.
Table 5-1 Command Sequence
Command
Number
of
writes
1
st
time
2
nd
time
3
rd
time
4
th
time
5
th
time
6
th
time
Address
[11:0]
Data
[7:0]
Address
[11:0]
Data
[7:0]
Address
[11:0]
Data
[7:0]
Address
[11:0]
Data
[7:0]
Address
[11:0]
Data
[7:0]
Address
[11:0]
Data
[7:0]
Reset
1
arbitrary F0
H
Read
1
RA
RD
Write
4
x554
H
AA
H
yAA8
H
55
H
x554
H
A0
H
PA
PD
Chip erase
6
x554
H
AA
H
yAA8
H
55
H
x554
H
80
H
x554
H
AA
H
yAA8
H
55
H
x554
H
10
H
Sector erase 6
x554
H
AA
H
yAA8
H
55
H
x554
H
80
H
x554
H
AA
H
yAA8
H
55
H
SA
30
H
Sector erase
suspend
1
arbitrary B0
H
Sector erase
resume
1
arbitrary 30
H
* : The data written in the table only shows the lower 8 bits. The upper 8 bits can be any value. The
commands are written as half-words or bytes.
* : The addresses written in the table only show the lower 16 bits. Set the upper 16 bits to any address
within the address range of the target flash macro.
x:1,3,5,7,9,B,D,F
y:0,2,4,6,8,A,C,E
PA: Write address (half-word aligned)
PA: Write address (half-word aligned)
PD: Write data (Write as half-word.)
SA: Sector address (specify an arbitrary address within the address range of the sector to erase.)
RA: Read address
RD: Read data (the read width is arbitrary.)
Note:
Do as follows to LSB 2-bit of the sector address (SA) to input when the command address and the sector
erase command are issued.
- When half-word access : 2'b00
- When byte access : 2’b01 or 2’b11
Example 1:
When byte access and command address = (LSB 2-bit of the standard command address is changed to
2’b01.)
yAA8
H
→ yAA9
H
, x554
H
→ x555
H
, and SA → { SA[31:2] and 2'b01 }
(SA: When the sector erase command is issued, it is an arbitrary address in the input erase target sector)
Example 2:
When byte access and command address = (LSB 2-bit of the standard command address is changed to
2’b11.)
yAA8
H
→ yAAB
H
, x554
H
→ x577
H
, and SA → { SA[31:2] and 2'b11 }
(SA: When the sector erase command is issued, it is an arbitrary address in the input erase target sector)
MB91520 Series
MN705-00010-1v0-E
1951