SH7211 Datasheet, PDF (988/1228 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family

Section 21 Flash Memory
When the new bit rate is selectable, the boot program returns an ACK code to the host and then
makes the register setting to select the new bit rate. The host then sends an ACK code at the
new bit rate, and the boot program responds to this with another ACK code, this time at the
new bit rate.
Acknowledge H'06
• Acknowledge H'06 (1 byte): The ACK code sent by the host to acknowledge the new bit rate.
Response
H'06
• Response H'06 (1 byte): The ACK code transferred in response to acknowledgement of the
new bit rate
The sequence of new bit rate selection is shown in figure 21.22.
Host
Wait for one-bit
period at the current
bit rate setting
Setting the new
bit rate
New bit rate setting
H'06 (ACK)
H'06 (ACK) at the new bit rate
H'06 (ACK) at the new bit rate
Boot program
New bit rate setting
Figure 21.22 Sequence of New Bit Rate Selection
Rev. 2.00 May. 08, 2008 Page 964 of 1200
REJ09B0344-0200