Mitsubishi microcomputers
M16C / 62 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Appendix Standard Serial I/O Mode (Flash Memory Version)
Status Register (SRD)
The status register indicates operating status of the flash memory and status such as whether an erase
operation or a program ended successfully or in error. It can be read by writing the read status register
command (7016). Also, the status register is cleared by writing the clear status register command (5016).
Table 1.31.2 gives the definition of each status register bit. After clearing the reset, the status register
outputs “8016”.
Table 1.31.2. Status register (SRD)
Definition
SRD0 bits
Status name
"1"
"0"
Write state machine (WSM) status
Reserved
Ready
Busy
SR7 (bit7)
SR6 (bit6)
SR5 (bit5)
-
-
Erase status
Terminated in error
Terminated normally
Program status
Block status after program
Reserved
Terminated in error
Terminated normally
SR4 (bit4)
SR3 (bit3)
Terminated in error
Terminated normally
SR2 (bit2)
-
-
-
-
-
-
Reserved
SR1 (bit1)
SR0 (bit0)
Reserved
Write State Machine (WSM) Status (SR7)
The write state machine (WSM) status indicates the operating status of the flash memory. When
power is turned on, “1” (ready) is set for it. The bit is set to “0” (busy) during an auto write or auto erase
operation, but it is set back to “1” when the operation ends.
Erase Status (SR5)
The erase status reports the operating status of the auto erase operation. If an erase error occurs, it is
set to “1”. When the erase status is cleared, it is set to “0”.
Program Status (SR4)
The program status reports the operating status of the auto write operation. If a write error occurs, it is
set to “1”. When the program status is cleared, it is set to “0”.
266
MITSUBISHI [ Mitsubishi Group ]
