SH7146 Datasheet, PDF (846/1022 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperH™ RISC engine Family

Section 19 Flash Memory
Host
H'00 (max. 30 times)
H'00 (bit rate matching complete)
H'55
H'E6 (response)
H'FF (error)
Boot program
Measures the
length of one bit
Figure 19.22 Sequence of Bit-Rate Matching
• Communications protocol
Formats in the communications protocol between the host and boot program after completion of
the bit-rate matching are as follows.
1. One-character command or one-character response
A command or response consisting of a single character used for an inquiry or the ACK code
indicating normal completion.
2. n-character command or n-character response
A command or response that requires n bytes of data, which is used as a selection command or
response to an inquiry. The length of programming data is treated separately below.
3. Error response
Response to a command in case of an error: two bytes, consisting of the error response and
error code.
4. 128-byte programming command
The command itself does not include data-size information. The data length is known from the
response to the command for inquiring about the programming size.
5. Response to a memory reading command
This response includes four bytes of size information.
Rev. 3.00 May 17, 2007 Page 802 of 974
REJ09B0229-0300