SH7055S Datasheet, PDF (846/1002 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7000 Series

Host
Boot Program
H'00 (30 times maximum)
H'00 (Completion of adjustment)
H'55
H'E6 (Response to boot)
H'FF (Error)
Measuring the
1-bit length
Figure 22.27 Bit-Rate-Adjustment Sequence
• Communications protocol
After adjustment of the bit rate, the protocol for serial communications between the host and
the boot program is as shown below.
(1) One-byte commands and one-byte responses
These commands and responses are comprised of a single byte. These consists of the inquiries
and ACK for successful completion.
(2) n-byte commands or n-byte responses
These commands and responses are comprised of n bytes of data. These are selections and
responses to inquiries.
The amount of programming data is not included under this heading because it is determined
in another command.
(3) Error response
The error response is a response to inquiries. It consists of an error response and an error code
and which take up two bytes.
(4) Programming of 128 bytes
The size is not specified in commands. The data size is indicated in response to the
programming unit inquiry.
(5) Memory read response
This response consists of four bytes of data.
Rev.2.0, 07/03, page 808 of 960