SH7125_08 Datasheet, PDF (636/774 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH™ RISC engine Family

Section 17 Flash Memory
• The start address in the user branch destination is set to the FUBRA parameter (general
register R5).
When the user branch processing is not required, 0 must be set to FUBRA.
When the user branch is executed, the branch destination is executed in flash memory
other than the one that is to be programmed. The area of the on-chip program that is
downloaded cannot be set.
The program processing must be returned from the user branch processing by the RTS
instruction.
See the description in section 17.4.3 (2.2), Flash user branch address setting parameter
(FUBRA: general register R5 of CPU).
(2.7) Initialization
When a programming program is downloaded, the initialization program is also downloaded to
on-chip RAM. There is an entry point of the initialization program in the area from (download
start address set by FTDAR) + 32 bytes. The subroutine is called and initialization is executed
by using the following steps.
MOV.L #DLTOP+32,R1
JSR @R1
NOP
; Set entry address to R1
; Call initialization routine
• The general registers other than R0 are saved in the initialization program.
• R0 is a return value of the FPFR parameter.
• Since the stack area is used in the initialization program, a stack area of maximum 128
bytes must be reserved in RAM.
• Interrupts can be accepted during the execution of the initialization program. However,
the program storage area and stack area in on-chip RAM and register values must not
be destroyed.
(2.8) The return value of the initialization program, FPFR (general register R0) is checked.
(2.9) FKEY must be set to H'5A and the user MAT must be prepared for programming.
(2.10) The parameter which is required for programming is set.
The start address of the programming destination of the user MAT (FMPAR) is set to general
register R5. The start address of the program data storage area (FMPDR) is set to general
register R4.
• FMPAR setting
FMPAR specifies the programming destination start address. When an address other
than one in the user MAT area is specified, even if the programming program is
executed, programming is not executed and an error is returned to the return value
Rev. 4.00 Jul. 25, 2008 Page 616 of 750
REJ09B0243-0400