SH7211 Datasheet, PDF (946/1228 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family

Section 21 Flash Memory
(2) State Transition Diagram
Figure 21.8 gives an overview of the state transitions after the chip has been started up in boot
mode. For details on boot mode, see section 21.8.1, Specifications of the Standard Serial
Communications Interface in Boot Mode.
1. Bit-rate matching
After the chip has been started up in boot mode, bit-rate matching between the SCI and the
host proceeds.
2. Waiting for inquiry and selection commands
The chip sends the requested information to the host in response to inquiries regarding the size
and configuration of the user MAT, start addresses of the MATs, information on supported
devices, etc.
3. Automatic erasure of the entire user MAT and user boot MAT
After all necessary inquiries and selections have been made and the command for transition to
the programming/erasure state is sent by the host, the entire user MAT and user boot MAT are
automatically erased.
4. Waiting for programming/erasure command
⎯ On receiving the programming selection command, the chip waits for data to be
programmed. To program data, the host transmits the programming command code
followed by the address where programming should start and the data to be programmed.
This is repeated as required while the chip is in the programming-selected state. To
terminate programming, H'FFFFFFFF should be transmitted as the first address of the area
for programming. This makes the chip return to the programming/erasure command
waiting state from the programming data waiting state.
⎯ On receiving the erasure select command, the chip waits for the block number of a block to
be erased. To erase a block, the host transmits the erasure command code followed by the
number of the block to be erased. This is repeated as required while the chip is in the
erasure-selected state. To terminate erasure, H'FF should be transmitted as the block
number. This makes the chip return to the programming/erasure command waiting state
from the erasure block number waiting state. Erasure should only be executed when a
specific block is to be reprogrammed without executing a reset-start of the chip after the
flash memory has been programmed in boot mode. If all desired programming is done in a
single operation, such erasure processing is not necessary because all blocks are erased
before the chip enters the programming/erasure/other command waiting state.
⎯ In addition to the programming and erasure commands, commands for sum checking and
blank checking (checking for erasure) of the user MAT and user boot MAT, reading data
from the user MAT/user boot MAT, and acquiring current state information are provided.
Rev. 2.00 May. 08, 2008 Page 922 of 1200
REJ09B0344-0200