D12320VF25V Datasheet, PDF (790/1146 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 17 ROM
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 17.83 Bit-Rate-Adjustment Sequence
Communications Protocol
After adjustment of the bit rate, the protocol for 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 are consists of the
inquiries and the 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 comes two bytes.
(4) Programming of n bytes
The size is not specified in commands. The size of n is indicated in response to the
programming unit inquiry.
(5) Memory read response
This response consists of four bytes of data.
Rev.7.00 Feb. 14, 2007 page 756 of 1108
REJ09B0089-0700