Datasheet

Section 22 Flash Memory
R01UH0309EJ0500 Rev. 5.00 Page 1169 of 1408
Sep 24, 2012
H8S/2456, H8S/2456R, H8S/2454 Group
(2) State Transition Diagram
The state transition after USB boot mode is initiated is shown in figure 22.9.
Boot mode initiation
(reset by boot mode)
All user ROM erasure
Enumeration
Inquiry command reception
Inquiry command response
H'55 reception
Processing of inquiry
setting command
Wait for inquiry
setting command
Read/check command reception
Command response
(Programming
completion)
(Program selection
command reception)
(Erasure completion)
(Erasure selection
command reception)
(Program data transmission)
Processing of
read/check command
Wait for inquiry
programming/erasing
command
Wait for program data
Wait for erasure block data
1.
2.
3.
4.
Figure 22.9 USB Boot Mode State Transition Diagram
1. After a transition to the USB boot mode is made, the boot program embedded in this LSI is
initialized. This LSI performs enumeration to the host after the USB boot program is
initialized.
2. Inquiry information about the size, configuration, start address, and support status of the user
ROM is transmitted to the host.
3. After inquiries have finished, all user ROMs are automatically erased.