R8C/13 Group
17.4 CPU Rewrite Mode
17.4.3 Software Commands
Software commands are described below. The command code and data must be read and written in
8-bit units.
Table 17.4 Software Commands
First bus cycle
Address
Second bus cycle
Address
Command
Data
to D
Data
to D0)
Mode
Mode
Read
(D
7
0
)
(D
7
Write
Write
Write
Write
Write
Read array
X
X
FF16
7016
5016
4016
2016
X
SRD
Read status register
Clear status register
Program
X
WA
BA
WD
WA
X
Write
Write
Block erase
D016
SRD: Status register data (D7 to D0)
WA: Write address (Make sure the address value specified in the the first bus cycle is the same address
as the write address specified in the second bus cycle.)
WD: Write data (8 bits)
BA: Given block address
X: Any address in the user ROM area
• Read Array Command
This command reads the flash memory.
Writing ‘FF16’ in the first bus cycle places the microcomputer in read array mode. Enter the read
address in the next or subsequent bus cycles, and the content of the specified address can be read
in 8-bit units.
Because the microcomputer remains in read array mode until another command is written, the con-
tents of multiple addresses can be read in succession.
• Read Status Register Command
This command reads the status register.
Write ‘7016’ in the first bus cycle, and the status register can be read in the second bus cycle. (Refer
to Section 17.4.4, “Status Register.”) When reading the status register too, specify an address in the
user ROM area.
Avoid executing this command in EW1 mode.
• Clear Status Register Command
This command sets the status register to “0”.
Write ‘5016’ in the first bus cycle, and the FMR06 to FMR07 bits in the FMR0 register and SR4 to SR5
in the status register will be set to “0”.
Rev.1.20 Jan 27, 2006 page 175 of 205
REJ09B0111-0120
RENESAS [ RENESAS TECHNOLOGY CORP ]
