Datasheet

Section 16 USB Function Module (USB)
Page 988 of 1408 R01UH0309EJ0500 Rev. 5.00
Sep 24, 2012
H8S/2456, H8S/2456R, H8S/2454 Group
16.5 Operation
16.5.1 Initial Settings
USB function
48-MHz USB clock
supply started
Application
Set the multiplication ratio for the USB
PLL frequency.
(USSTC1 and USSTC0 in USPLLCR)
With a software timer, and so on, wait for
48-MHz USB clock oscillation to be
settled. (t
USOSC
)
Cancel 48-MHz USB clock module
stop mode.
(Clear MSTP17 in EXMSTPCRL to 0.)
Cancel USB system clock module
stop mode.
(Clear MSTP18 in EXMSTPCRL to 0.)
Cancel reset state in the protocol
processing block.
(Clear PRTRST in CTLR to 0.)
Wait for USB cable connection.
Power-on reset state canceled
Set the endpoint information to
endpoint information register (EPIR).
Insert a 26-state dummy cycle.
Figure 16.2 Initial Setting Operation