Software Commands - Renesas R8C/18 Series Hardware Manual

R8C/18 Group, R8C/19 Group
17.4.3

Software Commands

The software commands are described below. Read or write commands and data in 8-bit units.
Table 17.4 Software Commands
Command
Read array
Read status register
Clear status register
Program
Block erase
SRD: Status register
WA: Write address (ensure the address specified in 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
×: Any specified address in the user ROM area
17.4.3.1 Read Array Command
The read array command reads the flash memory.
The MCU enters read array mode when FFh is written in the first bus cycle. When the read address is
entered in the following bus cycles, the content of the specified address can be read in 8-bit units.
Since the MCU remains in read array mode until another command is written, the contents of multiple
addresses can be read continuously.
17.4.3.2 Read Status Register Command
The read status register command is used to read the status register.
When 70h is written in the first bus cycle, the status register can be read in the second bus cycle.
(Refer to 17.4.4 Status Register.) When reading the status register, specify an address in the user
ROM area.
Do not execute this command in EW1 mode.
17.4.3.3 Clear Status Register Command
The clear status register command sets the status register to 0.
When 50h is written in the first bus cycle, bits FMR06 to FMR07 in the FMR0 register and SR4 to SR5
in the status register are set to 0.
Rev.1.30 Apr 14, 2006
REJ09B0222-0130
First Bus Cycle
Mode Address
Write ×
Write ×
Write ×
Write WA
Write ×
data (D7 to D0)
Page 188 of 233
Data
Mode
(D7 to D0)
FFh
70h Read
50h
40h Write
20h Write
17. Flash Memory Version
Second Bus Cycle
Data
Address
D7 to D0)
(
× SRD
WA WD
BA D0h