Notes; Boot Related Pins; Operation When An Exception Occurs With The Exception Vector Set To The High Vector Address; Notes On Serial Flash Booting (Boot Mode 1) After This Lsi Is Reset - Renesas RZ/A Series User Manual

RZ/A1L Group, RZ/A1LU Group, RZ/A1LC Group
3.6

Notes

3.6.1

Boot Related Pins

The initial states and output states in deep standby mode of the pins related to CS0 space memory read, SPI multi I/O bus
space memory read, channel 0 of the SD host interface, and the MMC host interface are different in each boot mode.
For details, refer to section 8, Bus State Controller, section 41, Ports, and section 42, Power-Down Modes.
3.6.2 Operation when an Exception Occurs with the Exception Vector
Set to the High Vector Address
In this LSI, the program counter loops to its own address (exception vector address) in the on-chip ROM if an exception
(except for a reset) occurs when the exception vector is set to the high vector address. In boot mode 1, 2, or 3, set the V
bit in SCTLR to 0 to set the exception vector to the low vector address before an exception (except for a reset) occurs.
For the details about the CP15 system control register (SCTLR), refer to the Arm Architecture Reference Manual.
3.6.3

Notes on Serial Flash Booting (Boot Mode 1) after This LSI is Reset

In booting up from serial flash memory (boot mode 1), read commands (opcode: 03H, address: 3 bytes, dummy cycles:
none) are set for sending to the serial flash memory. Therefore, if this chip enters the reset state while the serial flash
memory cannot accept read commands, correct booting up of the chip may not be possible. For example, if the chip is
reset while the serial flash memory is being erased (placing it in the busy state), the serial flash memory will not accept
read commands. In such cases, that is, in system configurations where the chip may be reset while the serial flash
memory is unable to accept read commands, ensure that the serial flash memory is able to accept read commands after
the chip is released from the reset state by using serial flash memory that has its own reset pin or cutting off power to the
serial flash memory when a reset occurs.
R01UH0437EJ0600 Rev.6.00
Jan 29, 2021
3. Boot Mode
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