RX610 Group
26. ROM (Flash Memory for Code Storage)
R01UH0032EJ0120 Rev.1.20
Page 846 of 1006
Feb 20, 2013
26.6
Programming and Erasing the ROM
The ROM is programmed and erased by issuing commands to a dedicated sequencer (FCU) for programming and erasure.
The FCU has five modes. For programming and erasure, the mode is changed and then commands for programming and
erasure are issued.
The mode transitions required to program or erase the ROM and the system of commands are described below. The
descriptions apply in common to boot, user-boot, and single-chip mode (with on-chip ROM enabled), and to
on-chip-ROM-enabled expansion mode.
26.6.1
FCU Modes
The FCU has five modes or sets of modes. Transitions between modes are caused by modifying FENTRYR or issuing
FCU commands. Figure 26.5 is a diagram of the FCU mode transitions.
ROM P/E mode
ROM status read
mode
(B)
(A)
ROM P/E normal
mode
ROM lock bit read
mode
(C)
(B)
(A)
(C)
Data flash P/E mode
ROM/data flash
read mode
FENTRYR = 0080h
FENTRYR = 0000h
ROM read mode
FENTRYR = 0000h
(A): Execute a normal mode transition command.
(B): Execute a command that is neither a normal mode transition command nor a lock bit read mode transition command.
(C): Execute a lock bit read mode transition command.
FENTRYR = 0001h
or
FENTRYR = 0002h
[Legend]
Figure 26.5 Mode Transitions of the FCU (Associated with the ROM)
Summary of Contents for RX600 Series
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