m37516e6hp Renesas Electronics Corporation., m37516e6hp Datasheet - Page 56

• Manufacturer Part Number: m37516e6hp
• Description: Single-chip 8-bit Cmos Microcomputer
• Manufacturer: Renesas Electronics Corporation.

7516 Group
Software Commands (CPU Rewrite Mode)
Table 14 lists the software commands.
After setting the CPU Rewrite Mode Select Bit of the flash memory
control register to “1”, execute a software command to specify an
erase or program operation.
Each software command is explained below.
The read array mode is entered by writing the command code
“FF
one of the bus cycles that follow, the contents of the specified ad-
dress are read out at the data bus (D
The read array mode is retained intact until another command is
written.
The read status register mode is entered by writing the command
code “70
ter are read out at the data bus (D
bus cycle.
The status register is explained in the next section.
This command is used to clear the bits SR1, SR4, and SR5 of the
status register after they have been set. These bits indicate that
operation has ended in an error. To use this command, write the
command code “50
Program operation starts when the command code “40
ten in the first bus cycle. Then, if the address and data to program
are written in the 2nd bus cycle, program operation (data program-
ming and verification) will start.
Whether the write operation is completed can be confirmed by
reading the status register or the RY/BY Status Flag of the flash
memory control register. When the program starts, the read status
Table 14 List of software commands (CPU rewrite mode)
Rev.1.01
Notes 1: X denotes a given address in the User ROM area .
Read Array Command (FF
Read Status Register Command (70
Clear Status Register Command (50
Program Command (40
R e a d a r r a y
R e a d s t a t u s r e g i s t e r
Clear status register
P r o g r a m
Erase all blocks
B l o c k e r a s e
16
” in the first bus cycle. When an address to be read is input in
2: SRD = Status Register Data
3: WA = Write Address, WD = Write Data
4: BA = Block Address to be erased (Input the maximum address of each block.)
16
” in the first bus cycle. The contents of the status regis-
Jul 01, 2003
Command
16
” in the first bus cycle.
16
)
page 54 of 89
16
)
0
to D
0
_____
to D
16
7
16
) by a read in the second
C y c l e n u m b e r
)
)
7
).
1
2
1
2
2
2
16
” is writ-
Mode
W r i t e
W r i t e
Write
W r i t e
Write
W r i t e
Address
register mode is entered automatically and the contents of the sta-
tus register is read at the data bus (D
bit 7 (SR7) is set to “0” at the same time the write operation starts
and is returned to “1” upon completion of the write operation. In
this case, the read status register mode remains active until the
next command is written.
The RY/BY Status Flag is “0” (busy) during write operation and “1”
(ready) when the write operation is completed as is the status reg-
ister bit 7.
At program end, program results can be checked by reading bit 4
(SR4) of the status register.
Fig. 60 Program flowchart
X
First bus cycle
(Note 1)
X
X
X
X
X
W r i t e
(Read array command
____
Program completed
( D
S t a t u s r e g i s t e r
“FF
W r i t e 4 0
S R 4 = 0 ?
D a t a
0
W r i t e a d d r e s s
W r i t e d a t a
R Y / B Y = 1 ?
S R 7 = 1 ?
t o D
F F
7 0
4 0
20
2 0
50
S t a r t
r e a d
16
1 6
1 6
16
1 6
1 6
16
o r
” write)
7
)
Y E S
Y E S
1 6
Mode
R e a d
W r i t e
Write
W r i t e
NO
NO
S e c o n d b u s c y c l e
W A
B A
0
A d d r e s s
to D
X
(Note 4)
X
(Note 3)
7
). The status register
P r o g r a m
e r r o r
S R D
W D
(D
0
Data
20
D 0
to D
(Note 2)
( N o t e 3 )
16
1 6
7
)