RX610 Group
26. ROM (Flash Memory for Code Storage)
R01UH0032EJ0120 Rev.1.20
Page 833 of 1006
Feb 20, 2013
FENTRY0 Bit (ROM P/E Mode Entry 0)
This bit is used to place 1 Mbyte of ROM (read addresses: FFF0 0000h to FFFF FFFFh, programming/erasure addresses
00F0 0000h to 00FF FFFFh) in P/E mode.
[Writing-enable conditions (when all of the following conditions are met)]
•
On-chip ROM is enabled.
•
The FRDY bit in FSTATR0 is set to 1.
•
AAh is written to the FEKEY[7:0] bits in word access.
[Setting condition]
•
When the writing-enable conditions are met, FENTRYR is set to 0000h, and 1 is written to the FENTRY0 bit
[Clearing conditions]
•
Data is written in byte access.
•
Data is written in word access when the FEKEY[7:0] bits are other than AAh.
•
When the writing-enable conditions are met, 0 is written to the FENTRY0 bit.
•
When the writing-enable conditions are met and FENTRYR is other than 0000h, data is written to FENTRYR.
FENTRY1 Bit
*
(ROM P/E Mode Entry 1)
This bit is used to place 1 Mbyte of ROM (read addresses: FFE0 0000h to FFEF FFFFh, programming/erasure addresses
00E0 0000h to 00EF FFFFh) in P/E mode.
[Writing-enable conditions (when all of the following conditions are met)]
•
On-chip ROM is enabled.
•
The FRDY bit in FSTATR0 is set to 1.
•
AAh is written to the FEKEY[7:0] bits in word access.
[Setting condition]
•
When the writing-enable conditions are met, FENTRYR is set to 0000h, and 1 is written to the FENTRY1 bit*
[Clearing conditions]
•
Data is written in byte access.
•
Data is written in word access when the FEKEY[7:0] bits are other than AAh.
•
When the writing-enable conditions are met, 0 is written to the FENTRY1 bit*.
•
When the writing-enable conditions are met and FENTRYR is other than 0000h, data is written to FENTRYR.
Note: * Cannot be used in a product whose ROM size is equal to or smaller than 1 Mbyte.