SH7280 Datasheet, PDF (1466/1726 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine family

Section 26 Flash Memory
Download and initialization are performed only once at the beginning.
In this kind of operation, note the following:
1. Be careful not to destroy on-chip RAM with overlapped settings.
In addition to the erasing program area and programming program area, 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.
2. 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'FFF81020 in this example) and (download start address for programming program) + 32
bytes (H'FFF82000 in this example).
26.5.4 User Boot Mode (SH7286 and SH7285)
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.
In addition, the user boot mode is not available in the SH7243.
(1) User Boot Mode Initiation
For the mode pin settings to start up user boot mode, see table 26.1.
When the reset start is executed in user boot mode, the check routine for flash-memory related
registers runs on the on-chip RAM. NMI and all other interrupts cannot be accepted. Neither can
the AUD be used in this period. This period is 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.
Rev. 1.00 Jun. 26, 2008 Page 1436 of 1692
REJ09B0393-0100