UM10562 Datasheet, PDF (412/942 Pages) NXP Semiconductors – LPC408x/407x User manual

NXP Semiconductors
UM10562
Chapter 14: LPC408x/407x USB OTG controller
idle
B_HNP_TRACK = 0
no
B_HNP_TRACK = 1 ?
no
bus suspended ?
disconnect device controller from U1
set REMOVE_PU
set HNP_FAILURE,
clear B_HNP_TRACK,
clear PU_REMOVED
no
PU_REMOVED set?
yes
PU_REMOVED set?
bus reset/resume detected?
yes
no
wait 25 s for bus to settle
reconnect port U1 to the
device controller
reconnect port U1 to the
device controller
yes
connect from A-device detected?
no
yes
bus reset/resume detected?
no
set HNP_SUCCESS
set PORT_FUNC[0]
drive J on internal host controller port
and SE0 on U1
SE0 sent by host?
no
yes
connect U1 to host controller
clear B_HNP_TRACK
clear PU_REMOVED
Fig 56. Hardware support for B-device switching from peripheral state to host state
UM10562
User manual
Figure 57 shows the actions that the OTG software stack should take in response to the
hardware actions setting REMOVE_PU, HNP_SUCCESS, AND HNP_FAILURE. The
relationship of the software actions to the Dual-Role B-Device states is also shown.
B-device states are in bold font with a circle around them.
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 13 September 2012
© NXP B.V. 2012. All rights reserved.
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