RX610 Group
26. ROM (Flash Memory for Code Storage)
R01UH0032EJ0120 Rev.1.20
Page 863 of 1006
Feb 20, 2013
(8) Reading Lock Bits
Lock bits can be read out by either reading from a memory area or reading from a register.
The lock bit read 2 command is issued in the case of the register-reading method (i.e. when the FRDMD bit in FMODR
is 1). This command is issued to an address within the block for which the lock bit is to be read out; the address range is
that for programming and erasing the ROM. In the first and second cycles of the lock bit read 2 command, the values 71h
and D0h are written as bytes; once these values have been written, the value of the lock bit for the specified erasure block
is copied to the FLOCKST bit in FSTATR1.
In the case of the memory area reading method (i.e. when the FRDMD bit in FMODR is 0), the FCU is placed in lock-bit
reading mode, and the lock bit is obtained by reading from an address within the address range for programming and
erasure of the ROM. Details are given in section 26.6.4.1 (5)Switching to ROM Lock-Bit Read Mode.
FRDY bit check
Write D0h to arbitrary address in
erasure block in byte access
FRESETR.FRESET = 1
writing
Wait
(tRESW2)
*
FRESETR.FRESET = 0
writing
FCU initialization
No
Yes
Timeout
(10
µ
s)
"0"
"1"
Note:
*
tRESW2: Reset pulse width during programming/erasure (see section 29, Electrical Characteristics)
ILGLERR bit check
FLOCKST bit check
Write 71h to ROM programming/
erasure address in byte access
Issue a lock bit read 2 command
Use the ROM programming/erasure address
(Do not use a read address)
Start
End
Figure 26.17 Procedure for Reading Lock Bit in Register Read Mode
Summary of Contents for RX600 Series
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