R8C/1A Group, R8C/1B Group
18. Flash Memory
Rev.1.30
Dec 08, 2006
Page 266 of 315
REJ09B0252-0130
18.4.4
Status Register
The status register indicates the operating status of the flash memory and whether an erase or program operation
has completed normally or in error. Status of the status register can be read by bits FMR00, FMR06, and
FMR07 in the FMR0 register.
Table 18.5 lists the Status Register Bits.
In EW0 mode, the status register can be read in the following cases:
•
When a given address in the user ROM area is read after writing the read status register command
•
When a given address in the user ROM area is read after executing program or block erase command but
before executing the read array command.
18.4.4.1
Sequencer Status (Bits SR7 and FMR00)
The sequencer status bits indicate the operating status of the flash memory. SR7 is set to 0 (busy) during
auto-programming and auto-erasure, and is set to 1 (ready) at the same time the operation completes.
18.4.4.2
Erase Status (Bits SR5 and FMR07)
Refer to
18.4.5 Full Status Check
.
18.4.4.3
Program Status (Bits SR4 and FMR06)
Refer to
18.4.5 Full Status Check
.
D0 to D7: Indicate the data bus which is read when the read status register command is executed.
Bits FMR07 (SR5) to FMR06 (SR4) are set to 0 by executing the clear status register command.
When the FMR07 bit (SR5) or FMR06 bit (SR4) is set to 1, the program and block erase commands cannot
be accepted.
Table 18.5
Status Register Bits
Status
Register
Bit
FMR0
Register
Bit
Status Name
Description
Value
after
Reset
0
1
SR0 (D0)
−
Reserved
−
−
−
SR1 (D1)
−
Reserved
−
−
−
SR2 (D2)
−
Reserved
−
−
−
SR3 (D3)
−
Reserved
−
−
−
SR4 (D4)
FMR06
Program status Completed
normally
Error
0
SR5 (D5)
FMR07
Erase status
Completed
normally
Error
0
SR6 (D6)
−
Reserved
−
−
−
SR7 (D7)
FMR00
Sequencer
status
Busy
Ready
1