Renesas 16-bit single-chip microcomputer Computer Hardware User Manual


 
Rev.1.02 Jul 01, 2005 page 251 of 314
REJ09B0126-0102
M16C/6N Group (M16C/6NL, M16C/6NN) 20. Flash Memory Version
Under development
This document is under development and its contents are subject to change.
20.3.5.8 Read Lock Bit Status Command (71h)
The read lock bit status command reads the lock bit state of a specified block.
By writing xx71h in the first bus cycle and xxD0h to the highest-order even address of a block in the
second bus cycle, the FMR16 bit in the FMR1 register stores information on whether or not the lock bit
of a specified block is locked. Read the FMR16 bit after the FMR00 bit in the FMR0 register is set to 1
(ready).
Figure 20.11 shows a flow chart of the read lock bit status command programming.
Start
YES
NO
FMR00=1?
YES
NO
FMR16=0?
Write the command code "xx71h"
Write "xxD0h" to the highest-order
block address
Block is not locked
Block is locked
NOTE:
1.Write the command code and data to even addresses.
Figure 20.11 Read Lock Bit Status Command