SH7055S Datasheet, PDF (820/1002 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7000 Series

areas for the user procedure programs, work area, and stack area are reserved in on-chip RAM.
Do not make settings that will overwrite data in these areas.
• Be sure to initialize both the erasing program and programming program.
Initialization by setting the FPEFEQ and FUBRA parameters must be performed for both the
erasing program and the programming program. Initialization must be executed for both entry
addresses: (download start address for erasing program) + 32 bytes (H'FFFF7020 in this
example) and (download start address for programming program) + 32 bytes (H'FFFF7820 in
this example).
22.5.3 User Boot Mode
This LSI has user boot mode which is initiated with different mode pin settings than those in user
program mode or boot mode. User boot mode is a user-arbitrary boot mode, unlike boot mode that
uses the on-chip SCI.
Only the user MAT can be programmed/erased in user boot mode. Programming/erasing of the
user boot MAT is only enabled in boot mode or programmer mode.
(1) User Boot Mode Initiation
For the mode pin settings to start up user boot mode, see table 22.1, Relationship between
FWE and MD Pins and Operating Modes.
When the reset start is executed in user boot mode, the check routine for flash-memory related
registers runs. While the check routine is running, the RAM area about 1.2 kbytes from
H'FFFF6800 is used by the routine and 4 bytes from H'FFFFDFFC is used as a stack area.
NMI and all other interrupts cannot be accepted. Neither can the AUD be used in this period.
This period is approximately 100 µs while operating at an internal frequency of 40 MHz.
Next, processing starts from the execution start address of the reset vector in the user boot
MAT. At this point, H'AA is set to the flash MAT select register (FMATS) because the
execution MAT is the user boot MAT.
(2) User MAT Programming in User Boot Mode
For programming the user MAT in user boot mode, additional processings made by setting
FMATS are required: switching from user-boot-MAT selection state to user-MAT selection
state, and switching back to user-boot-MAT selection state after programming completes.
Figure 22.14 shows the procedure for programming the user MAT in user boot mode.
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