SH7059 Datasheet, PDF (757/1042 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

24. ROM (SH7058S)
Start _{D0 D1 D2 D3 D4 D5 D6}
bit
D7 ^{Stop bit}
Measure low period (9 bits) (data is H'00)
High period of
at least 1 bit
Figure 24.7 Automatic Adjustment Operation of SCI Bit Rate
Table 24.8 System Clock Frequency that Can Automatically Adjust Bit Rate of This LSI
Host Bit Rate
9,600 bps
19,200 bps
System Clock Frequency Which Can Automatically Adjust LSI's Bit Rate
40 to 80 MHz (input frequency of 5 to 10 MHz)
40 to 80 MHz (input frequency of 5 to 10 MHz)
(2) State Transition
The overview of the state transition after boot mode is initiated is shown in figure 24.8. For details on boot mode, see
section 24.10.1, Serial Communications Interface Specification for Boot Mode.
1. Bit rate adjustment
After boot mode is initiated, the bit rate of the SCI interface is adjusted with that of the host.
2. Waiting for inquiry set command
For inquiries about the user-MAT size and configuration, MAT start address, and support state, the required
information is transmitted to the host.
3. Automatic erasure of all user MAT and user boot MAT
After inquiries have finished, all of the user MAT and user boot MAT are automatically erased if a
programming/erasing status transition command is sent.
4. Waiting for programming/erasing command
• When the program selection command is received, the state for waiting program data is entered. The
programming start address and program data must be transmitted following the programming command. When
programming is finished, the programming start address must be set to H'FFFFFFFF and transmitted. Then the
state for waiting program data is returned to the state of programming/erasing command wait.
• When the erasure selection command is received, the state for waiting erase-block data is entered. The erase-
block number must be transmitted following the erasing command. When the erasure is finished, the erase-
block number must be set to H'FF and transmitted. Then the state for waiting erase-block data is returned to the
state for waiting programming/erasing command. The erasure must be executed when reset start is not executed
and the specified block is programmed after programming is executed in boot mode. When programming can
be executed by only one operation, all blocks are erased before the state for waiting programming/erasing/other
command is entered. The erasing operation is not required.
• There are many commands other than programming/erasing. Examples are checksum, blank check (erasure
check), and memory read of the user MAT/user boot MAT and acquisition of current status information.
Note that memory read of the user MAT/user boot MAT can only read the program data after all user MAT/user boot
MAT has automatically been erased.
Rev.3.00 Mar. 12, 2008 Page 667 of 948
REJ09B0177-0300