Boot Mode 2 - Renesas RZ/A Series User Manual

RZ/A1L Group, RZ/A1LU Group, RZ/A1LC Group
3.5.3

Boot Mode 2

In boot mode 2, booting up is from the NAND flash memory with the SD controller, which is connected to channel 0 of
the SD host interface. The flow of operation of this LSI in boot mode 4 is as described below.
After a power-on reset, this LSI executes the boot program stored in the on-chip ROM (starting from H'FFFF_0000).
The boot program transfers 28 Kbytes of program from the NAND flash memory with the SD controller connected to
channel 0 of the SD host interface to the address range from H'2002_4000 to H'2002_AFFF of the large-capacity on-chip
RAM.
The program (28 Kbytes) that the boot program transfers to the large-capacity on-chip RAM is called a loader program.
The boot program uses an area from H'2002_0000 to H'2002_3FFF as work memory. Note that the loader program must
be stored in the NAND flash memory with the SD controller according to the loader program storage specifications.*
Note 1. For the storage specifications of the loader program, contact Renesas Electronics Corporation's sales office.
After the boot program finishes processing, it branches to H'2002_4000 (large-capacity on-chip RAM). At this time, the
I bit, F bit, T bit and bits Mode[4:0] in CPSR are set to the initial states with the I bit set to 1'b1 (IRQ masked state), the
F bit set to 1'b1 (FIQ masked state), the T bit set to 1'b0 (Arm state) and bits Mode[4:0] set to 5'b10011 (supervisor
mode).
The size of the loader program that the boot program transfers to the large-capacity on-chip RAM is fixed to 28 Kbytes.
If your loader program exceeds this limit, use the loader program to transfer your program (application program) from
the NAND flash memory with the SD controller to the large-capacity on-chip or external RAM using channel 0 of the SD
host interface. Note that you must design a loader program.
R01UH0437EJ0600 Rev.6.00
Jan 29, 2021
3. Boot Mode
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