H8SXSLASH1663M datasheet(1189/1504 Pages) RENESAS

1189 / 1504 page

Section 25 Flash Memory

Rev. 2.00 Sep. 24, 2008 Page 1157 of 1468

REJ09B0412-0200

In figure 25.15, since RAM emulation is performed, the erasing/programming program is

downloaded to avoid the 4-Kbyte on-chip RAM area (H'FFA000 to H'FFAFFF). Download and

initialization are performed only once at the beginning. Note the following when executing the

procedure program.

• Be careful not to overwrite data in the on-chip RAM with overlay settings. In addition to the

programming program area, erasing program area, and RAM emulation area, areas for the

procedure programs, work area, and stack area are reserved in the on-chip RAM. Do not make

settings that will overwrite data in these areas.

• Be sure to initialize both the programming program and erasing program. When the FPEFEQ

parameter is initialized, also initialize both the erasing program and programming program.

Initialization must be executed for both entry addresses: #DLTOP (start address of download

destination for erasing program)

+ 32 bytes, and #DLTOP (start address of download

destination for programming program)

+ 32 bytes.

25.8.4

User Boot Mode

Branching to a programming/erasing program prepared by the user enables user boot mode which

is a user-arbitrary boot mode to be used.

Only the user MAT can be programmed/erased in user boot mode. Programming/erasure of the

user boot MAT is only enabled in boot mode or programmer mode.

(1)

Initiation in User Boot Mode

When the reset start is executed with the mode pins set to user boot mode, the built-in check

routine runs and checks the user MAT and user boot MAT states. While the check routine is

running, NMI and all other interrupts cannot be accepted. Next, processing starts from the

execution start address of the reset vector in the user boot MAT. At this point, the user boot MAT

is selected (FMATS = H'AA) as the execution memory MAT.

H8SX/1663M Datasheet(PDF) 1189 Page - Renesas Technology Corp